diff --git a/.travis.yml b/.travis.yml
index 7de708c..e3b64fa 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,4 +8,4 @@ before_script:
   - curl -s http://getcomposer.org/installer | php -- --quiet
   - php composer.phar install
 
-script: phpunit -c phpunit.dist.xml
+script: phpunit -c phpunit.xml.dist
diff --git a/README.md b/README.md
index 33925c1..ee152f0 100644
--- a/README.md
+++ b/README.md
@@ -8,11 +8,22 @@ A PHP 5.3+ library for generating and working with [RFC 4122][rfc4122] version
 Much inspiration for this library came from the [Java][javauuid] and
 [Python][pyuuid] UUID libraries.
 
+## Requirements
+
+*Rhumsaa\Uuid works on __64-bit builds__ of PHP 5.3.3+.*
+
+This library deals with large integers, so you will need to run it on a
+64-bit system with a 64-bit compiled version of PHP.
+
+**Warning:** The [Windows binaries located on PHP.net][phpwin] are 32-bit
+versions of PHP. Even if you run them on a 64-bit version of Windows, this
+library will not work. You will need to compile PHP on Windows yourself to
+build a 64-bit version.
+
 ## Examples
 
 ```php
 <?php
-
 use Rhumsaa\Uuid\Uuid;
 
 // Generate a version 1 (time-based) UUID
@@ -32,6 +43,148 @@ $uuid5 = Uuid::uuid5(Uuid::NAMESPACE_DNS, 'php.net');
 echo $uuid5 . "\n"; // c4a760a8-dbcf-5254-a0d9-6a4474bd1b62
 ```
 
+## Library API
+
+### Creation methods
+
+Each of the following methods are called statically to create Uuid objects. The
+class constructor cannot be used to create Uuid objects. That is, the use of
+`new Uuid()` is disabled.
+
+Uuid **Uuid::fromString($name)**  
+Creates a UUID from the string standard representation
+
+Example:
+
+    $uuid = Uuid::fromString('fa018870-d1f6-11e1-9b23-0800200c9a66');
+
+Uuid **Uuid::uuid1()**  
+Creates a time-based UUID (version 1)
+
+Uuid **Uuid::uuid3($namespace, $name)**  
+Creates a UUID (version 3) based on the MD5 hash of a namespace identifier and a name
+
+Uuid **Uuid::uuid4()**
+Creates a random UUID (version 4)
+
+Uuid **Uuid::uuid5($namespace, $name)**  
+Creates a UUID (version 5) based on the SHA-1 hash of a namespace identifier and a name
+
+### Instance methods
+
+Once you have a Uuid object, you may call the following methods on the object.
+
+int **compareTo(Uuid $uuid)**  
+Compares this UUID with the specified UUID. The first of two UUIDs is greater
+than the second if the most significant field in which the UUIDs differ is
+greater for the first UUID.
+
+Returns -1 if this UUID is less than the compared to UUID, 0 if it is equal to
+the compared to UUID, and 1 if it is greater than the compared to UUID.
+
+Example:
+
+    $uuid1 = Uuid::fromString('44cca71e-d13d-11e1-a959-c8bcc8a476f4');
+    $uuid2 = Uuid::fromString('44cca71e-d13d-11e2-a959-c8bcc8a476f4');
+    switch ($uuid1->$compareTo($uuid2)) {
+        case -1:
+            echo "$uuid1 is less than $uuid2";
+            break;
+        case 1:
+            echo "$uuid1 is greater than $uuid2";
+            break;
+        case 0:
+        default:
+            echo "$uuid1 is equal to $uuid2";
+    }
+
+bool **equals($obj)**  
+Compares this UUID to the specified object and returns `true` if they are equal.
+
+string **getBytes()**  
+Returns the UUID as a 16-byte string.
+
+int **getClockSeqHiAndReserved()**  
+Returns the high field of the clock sequence multiplexed with the variant
+(bits 65-72 of the UUID).
+
+int **getClockSeqLow()**  
+Returns the low field of the clock sequence (bits 73-80 of the UUID).
+
+int **getClockSequence()**  
+Returns the full clock sequence, including the high and low fields.
+
+\DateTime **getDateTime()**  
+For version 1 UUIDs, this returns a PHP DateTime object representing the date
+and time used to create the UUID.
+
+array **getFields()**  
+Returns an array of the fields of the UUID, with keys named according to the
+RFC 4122 names for the fields.
+
+| Field                      | Meaning                         |
+| -------------------------- | ------------------------------- |
+| time_low                   | the first 32 bits of the UUID   |
+| time_mid                   | the next 16 bits of the UUID    |
+| time_hi_and_version        | the next 16 bits of the UUID    |
+| clock_seq_hi_and_reserved  | the next 8 bits of the UUID     |
+| clock_seq_low              | the next 8 bits of the UUID     |
+| node                       | the last 48 bits of the UUID    |
+
+int **getLeastSignificantBits()**  
+Returns the least significant 64 bits of this UUID's 128 bit value.
+
+int **getMostSignificantBits()**  
+Returns the most significant 64 bits of this UUID's 128 bit value.
+
+int **getNode()**  
+Returns the node value associated with this UUID.
+
+int **getTimeHiAndVersion()**  
+Returns the high field of the timestamp multiplexed with the version number
+(bits 49-64 of the UUID).
+
+int **getTimeLow()**  
+Returns the low field of the timestamp (the first 32 bits of the UUID).
+
+int **getTimeMid()**  
+Returns the middle field of the timestamp (bits 33-48 of the UUID).
+
+int **getTimestamp()**  
+For version 1 UUIDs, this returns the 60 bit timestamp value used to create
+this UUID. The timestamp is measured in 100-nanosecond units since midnight,
+October 15, 1582, UTC. It is not a Unix timestamp.
+
+string **getUrn()**  
+Returns the string representation of the UUID as a URN.
+
+int **getVariant()**  
+Returns the variant number associated with this UUID.
+
+The variant number has the following meaning:
+
+* 0 - Reserved for NCS backward compatibility
+* 2 - The RFC 4122 variant (used by this class
+* 6 - Reserved, Microsoft Corporation backward compatibility
+* 7 - Reserved for future definition
+
+int **getVersion()**  
+The version number associated with this UUID. The version number describes how
+this UUID was generated.
+
+The version number has the following meaning:
+
+* 1 - Time-based UUID
+* 2 - DCE security UUID
+* 3 - Name-based UUID hashed with MD5
+* 4 - Randomly generated UUID
+* 5 - Name-based UUID hashed with SHA-1
+
+string **toString()**  
+Converts this UUID into a string representation. This class also implements
+__toString(), which will convert this object to a string when it is used in
+any string context.
+
 
 ## Installation
 
@@ -51,4 +204,5 @@ and install the latest version of the Uuid library into your project:
 [rfc4122]: http://tools.ietf.org/html/rfc4122
 [javauuid]: http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
 [pyuuid]: http://docs.python.org/library/uuid.html
+[phpwin]: http://windows.php.net/download/
 [packagist]: http://packagist.org/
diff --git a/composer.json b/composer.json
index 90bc282..24ef289 100644
--- a/composer.json
+++ b/composer.json
@@ -1,6 +1,6 @@
 {
     "name": "rhumsaa/uuid",
-    "description": "A PHP 5.3+ library for generating RFC 4122 version 1, 3, 4, and 5 universally unique identifiers (UUID).",
+    "description": "A PHP 5.3+ library for generating RFC 4122 version 1, 3, 4, and 5 universally unique identifiers (UUID). Requires a 64-bit build of PHP.",
     "type": "library",
     "keywords": ["uuid", "identifier", "guid"],
     "homepage": "https://github.com/ramsey/uuid",
@@ -18,7 +18,14 @@
     "require": {
         "php": ">=5.3.3"
     },
+    "require-dev": {
+        "doctrine/dbal": ">=2.3"
+    },
+    "suggest": {
+        "doctrine/dbal": "Allow the use of a UUID as doctrine field type."
+    },
     "autoload": {
         "psr-0": {"Rhumsaa\\Uuid": "src/"}
-    }
+    },
+    "minimum-stability": "dev"
 }
diff --git a/phpunit.dist.xml b/phpunit.xml.dist
similarity index 100%
rename from phpunit.dist.xml
rename to phpunit.xml.dist
diff --git a/src/Rhumsaa/Uuid/Doctrine/UuidType.php b/src/Rhumsaa/Uuid/Doctrine/UuidType.php
new file mode 100644
index 0000000..4c1fc5f
--- /dev/null
+++ b/src/Rhumsaa/Uuid/Doctrine/UuidType.php
@@ -0,0 +1,85 @@
+<?php
+/**
+ * This file is part of the Rhumsaa\Uuid library
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @copyright Copyright (c) 2012 Ben Ramsey <http://benramsey.com>
+ * @license http://opensource.org/licenses/MIT MIT
+ */
+
+namespace Rhumsaa\Uuid\Doctrine;
+
+use InvalidArgumentException;
+use Rhumsaa\Uuid\Uuid;
+use Doctrine\DBAL\Types\ConversionException;
+use Doctrine\DBAL\Types\Type;
+use Doctrine\DBAL\Platforms\AbstractPlatform;
+
+/**
+ * Field type mapping for the Doctrine Database Abstraction Layer (DBAL).
+ *
+ * UUID fields will be stored as a string in the database and converted back to
+ * the Uuid value object when querying.
+ */
+class UuidType extends Type
+{
+    /**
+     * @var string
+     */
+    const NAME = 'uuid';
+
+    /**
+     * @param array                                    $fieldDeclaration
+     * @param Doctrine\DBAL\Platforms\AbstractPlatform $platform
+     */
+    public function getSqlDeclaration(array $fieldDeclaration, AbstractPlatform $platform)
+    {
+        return $platform->getGuidTypeDeclartionSQL($fieldDeclaration);
+    }
+
+    /**
+     * @param string|null                              $value
+     * @param Doctrine\DBAL\Platforms\AbstractPlatform $platform
+     */
+    public function convertToPHPValue($value, AbstractPlatform $platform)
+    {
+        if (null === $value) {
+            return null;
+        }
+
+        try {
+            $uuid = Uuid::fromString($value);
+        } catch (InvalidArgumentException $e) {
+            throw ConversionException::conversionFailed($value, self::NAME);
+        }
+
+        return $uuid;
+    }
+
+    /**
+     * @param Uuid\Uuid|null                           $value
+     * @param Doctrine\DBAL\Platforms\AbstractPlatform $platform
+     */
+    public function convertToDatabaseValue($value, AbstractPlatform $platform)
+    {
+        if (empty($value)) {
+            return null;
+        }
+
+        if ($value instanceof Uuid) {
+            return (string) $value;
+        }
+
+        throw ConversionException::conversionFailed($value, self::NAME);
+    }
+
+    /**
+     * @return string
+     */
+    public function getName()
+    {
+        return self::NAME;
+    }
+}
diff --git a/src/Rhumsaa/Uuid/Uuid.php b/src/Rhumsaa/Uuid/Uuid.php
index 1565842..84815b3 100644
--- a/src/Rhumsaa/Uuid/Uuid.php
+++ b/src/Rhumsaa/Uuid/Uuid.php
@@ -97,6 +97,13 @@ final class Uuid
      */
     protected function __construct($msb, $lsb)
     {
+        if (PHP_INT_SIZE == 4) {
+            throw new \OverflowException(
+                'Attempting to create a UUID on a 32-bit build of PHP. This '
+                . 'library requires a 64-bit build of PHP.'
+            );
+        }
+
         $this->msb = $msb;
         $this->lsb = $lsb;
     }
diff --git a/tests/Rhumsaa/Uuid/Doctrine/UuidTypeTest.php b/tests/Rhumsaa/Uuid/Doctrine/UuidTypeTest.php
new file mode 100644
index 0000000..5a67b5c
--- /dev/null
+++ b/tests/Rhumsaa/Uuid/Doctrine/UuidTypeTest.php
@@ -0,0 +1,51 @@
+<?php
+namespace Rhumsaa\Uuid;
+
+use Doctrine\DBAL\Types\Type;
+use Doctrine\Tests\DBAL\Mocks\MockPlatform;
+use PHPUnit_Framework_TestCase;
+
+class UuidTypeTest extends PHPUnit_Framework_TestCase
+{
+    private $platform;
+    private $type;
+
+    public static function setUpBeforeClass()
+    {
+        Type::addType('uuid', 'Rhumsaa\Uuid\Doctrine\UuidType');
+    }
+
+    protected function setUp()
+    {
+        $this->platform = new MockPlatform();
+        $this->type = Type::getType('uuid');
+    }
+
+    public function testUuidConvertsToDatabaseValue()
+    {
+        $uuid = Uuid::fromString('ff6f8cb0-c57d-11e1-9b21-0800200c9a66');
+
+        $expected = $uuid->toString();
+        $actual = $this->type->convertToDatabaseValue($uuid, $this->platform);
+
+        $this->assertEquals($expected, $actual);
+    }
+
+    public function testUuidConvertsToPHPValue()
+    {
+        $uuid = $this->type->convertToPHPValue('ff6f8cb0-c57d-11e1-9b21-0800200c9a66', $this->platform);
+        $this->assertInstanceOf('Rhumsaa\Uuid\Uuid', $uuid);
+        $this->assertEquals('ff6f8cb0-c57d-11e1-9b21-0800200c9a66', $uuid->toString());
+    }
+
+    public function testInvalidUuidConversion()
+    {
+        $this->setExpectedException('Doctrine\DBAL\Types\ConversionException');
+        $this->type->convertToPHPValue('abcdefg', $this->platform);
+    }
+
+    public function testNullConversion()
+    {
+        $this->assertNull($this->type->convertToPHPValue(null, $this->platform));
+    }
+}
diff --git a/tests/Rhumsaa/Uuid/EnvironmentTest.php b/tests/Rhumsaa/Uuid/EnvironmentTest.php
new file mode 100644
index 0000000..f562b5d
--- /dev/null
+++ b/tests/Rhumsaa/Uuid/EnvironmentTest.php
@@ -0,0 +1,30 @@
+<?php
+namespace Rhumsaa\Uuid;
+
+/**
+ * This class tests the environment to ensure the library functions as designed
+ * on 32-bit and 64-bit environments.
+ */
+class EnvironmentTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Rhumsaa\Uuid\Uuid::__construct
+     */
+    public function testConstructorException()
+    {
+        if (PHP_INT_SIZE == 4) {
+
+            $this->setExpectedException(
+                'OverflowException',
+                'Attempting to create a UUID on a 32-bit build of PHP. This library requires a 64-bit build of PHP.'
+            );
+
+            $uuid = Uuid::uuid1();
+
+        } else {
+
+            $this->markTestSkipped('This test is only applicable on a 32-bit system.');
+
+        }
+    }
+}
diff --git a/tests/Rhumsaa/Uuid/UuidTest.php b/tests/Rhumsaa/Uuid/UuidTest.php
index 83e2e0d..0b22a3a 100644
--- a/tests/Rhumsaa/Uuid/UuidTest.php
+++ b/tests/Rhumsaa/Uuid/UuidTest.php
@@ -3,6 +3,16 @@ namespace Rhumsaa\Uuid;
 
 class UuidTest extends \PHPUnit_Framework_TestCase
 {
+    protected function setUp()
+    {
+        // Skip these tests if run on a 32-bit build of PHP
+        if (PHP_INT_SIZE == 4) {
+            $this->markTestSkipped(
+                'Running tests on a 32-bit build of PHP; 64-bit build required.'
+            );
+        }
+    }
+
     /**
      * @covers Rhumsaa\Uuid\Uuid::fromString
      * @covers Rhumsaa\Uuid\Uuid::__construct
@@ -497,10 +507,10 @@ class UuidTest extends \PHPUnit_Framework_TestCase
         // The next three UUIDs are used for comparing msb and lsb in
         // the compareTo() method
 
-        // msb are greater than $uuid4, lsb are greater than $uuid5
+        // msb are less than $uuid4, lsb are greater than $uuid5
         $uuid3 = Uuid::fromString('44cca71e-d13d-11e1-a959-c8bcc8a476f4');
 
-        // msb are less than in $uuid3, lsb are equal to those in $uuid3
+        // msb are greater than $uuid3, lsb are equal to those in $uuid3
         $uuid4 = Uuid::fromString('44cca71e-d13d-11e2-a959-c8bcc8a476f4');
 
         // msb are equal to those in $uuid3, lsb are less than in $uuid3
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 19834b8..447d18b 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -9,5 +9,6 @@ if (!file_exists(dirname(__DIR__) . DIRECTORY_SEPARATOR . 'composer.lock')) {
 }
 
 // Include the Composer autoloader
-include realpath(dirname(__FILE__) . '/../vendor/autoload.php');
+$loader = include realpath(dirname(__FILE__) . '/../vendor/autoload.php');
 
+$loader->add("Doctrine\Tests\DBAL", __DIR__."/../vendor/doctrine/dbal/tests");