diff --git a/src/Monolog/Log.php b/src/Monolog/Log.php
index f3bd7319..fee20292 100644
--- a/src/Monolog/Log.php
+++ b/src/Monolog/Log.php
@@ -19,7 +19,7 @@ class Log
     protected $name;
     protected $writers;
 
-    public function __construct($name, $level = Logger::WARN, $writers = array())
+    public function __construct($name, $level = Logger::WARNING, $writers = array())
     {
         $this->name = $name;
         $this->level = $level;
diff --git a/src/Monolog/Logger.php b/src/Monolog/Logger.php
index 2c4b0959..27f8767b 100644
--- a/src/Monolog/Logger.php
+++ b/src/Monolog/Logger.php
@@ -13,18 +13,16 @@ namespace Monolog;
 
 class Logger
 {
-    const DEBUG = 1;
-    const INFO = 5;
-    const WARN = 10;
-    const ERROR = 15;
-    const FATAL = 20;
+    const DEBUG   = 100;
+    const INFO    = 200;
+    const WARNING = 300;
+    const ERROR   = 400;
 
     protected static $levels = array(
-        1 => 'DEBUG',
-        5 => 'INFO',
-        10 => 'WARN',
-        15 => 'ERROR',
-        20 => 'FATAL',
+        100 => 'DEBUG',
+        200 => 'INFO',
+        300 => 'WARNING',
+        400 => 'ERROR',
     );
 
     protected $logs;
@@ -69,7 +67,7 @@ class Logger
 
     public function addWarning($message, $log = null)
     {
-        $this->addMessage(self::WARN, $message, $log);
+        $this->addMessage(self::WARNING, $message, $log);
     }
 
     public function addError($message, $log = null)
@@ -101,7 +99,7 @@ class Logger
 
     public function warn($message, $log = null)
     {
-        $this->addMessage(self::WARN, $message, $log);
+        $this->addMessage(self::WARNING, $message, $log);
     }
 
     public function err($message, $log = null)
diff --git a/tests/Monolog/Formatter/SimpleFormatterTest.php b/tests/Monolog/Formatter/SimpleFormatterTest.php
index 5dd310c5..588cd066 100644
--- a/tests/Monolog/Formatter/SimpleFormatterTest.php
+++ b/tests/Monolog/Formatter/SimpleFormatterTest.php
@@ -18,18 +18,18 @@ class SimpleFormatterTest extends \PHPUnit_Framework_TestCase
     public function testDefFormatWithString()
     {
         $formatter = new SimpleFormatter(null, 'Y-m-d');
-        $message = $formatter->format('log', Logger::WARN, 'foo');
-        $this->assertEquals('['.date('Y-m-d').'] log.WARN: foo'."\n", $message);
+        $message = $formatter->format('log', Logger::WARNING, 'foo');
+        $this->assertEquals('['.date('Y-m-d').'] log.WARNING: foo'."\n", $message);
     }
 
     public function testDefFormatWithArray()
     {
         $formatter = new SimpleFormatter(null, 'Y-m-d');
-        $message = $formatter->format('xx', Logger::FATAL, array(
+        $message = $formatter->format('xx', Logger::ERROR, array(
             'log' => 'log',
-            'level' => 'WARN',
+            'level' => 'WARNING',
             'message' => 'foo'
         ));
-        $this->assertEquals('['.date('Y-m-d').'] log.WARN: foo'."\n", $message);
+        $this->assertEquals('['.date('Y-m-d').'] log.WARNING: foo'."\n", $message);
     }
 }
diff --git a/tests/Monolog/LogTest.php b/tests/Monolog/LogTest.php
index 34bdfe8e..0a9e87da 100644
--- a/tests/Monolog/LogTest.php
+++ b/tests/Monolog/LogTest.php
@@ -19,26 +19,26 @@ class LogTest extends \PHPUnit_Framework_TestCase
         $writer1 = $this->getMock('Monolog\Writer\NullWriter', array('write'));
         $writer1->expects($this->once())
             ->method('write')
-            ->with('bob', Logger::WARN, 'test');
+            ->with('bob', Logger::WARNING, 'test');
         $writer2 = $this->getMock('Monolog\Writer\NullWriter', array('write'));
         $writer2->expects($this->once())
             ->method('write')
-            ->with('bob', Logger::WARN, 'test');
+            ->with('bob', Logger::WARNING, 'test');
         $logger->addWriter($writer1);
         $logger->addWriter($writer2);
-        $logger->addMessage(Logger::WARN, 'test');
+        $logger->addMessage(Logger::WARNING, 'test');
     }
 
     public function testLogLowLevel()
     {
         $logger = new Log('bob');
-        $logger->setLevel(Logger::FATAL);
-        $this->assertEquals(Logger::FATAL, $logger->getLevel());
+        $logger->setLevel(Logger::ERROR);
+        $this->assertEquals(Logger::ERROR, $logger->getLevel());
 
         $writer1 = $this->getMock('Monolog\Writer\NullWriter', array('write'));
         $writer1->expects($this->never())
             ->method('write');
         $logger->addWriter($writer1);
-        $logger->addMessage(Logger::WARN, 'test');
+        $logger->addMessage(Logger::WARNING, 'test');
     }
 }
diff --git a/tests/Monolog/Writer/StreamWriterTest.php b/tests/Monolog/Writer/StreamWriterTest.php
index 7ff7726a..9ac51c59 100644
--- a/tests/Monolog/Writer/StreamWriterTest.php
+++ b/tests/Monolog/Writer/StreamWriterTest.php
@@ -19,9 +19,9 @@ class StreamWritterTest extends \PHPUnit_Framework_TestCase
     {
         $handle = fopen('php://memory', 'a+');
         $writer = new StreamWriter($handle);
-        $writer->write('log', Logger::WARN, 'test');
-        $writer->write('log', Logger::WARN, 'test2');
-        $writer->write('log', Logger::WARN, 'test3');
+        $writer->write('log', Logger::WARNING, 'test');
+        $writer->write('log', Logger::WARNING, 'test2');
+        $writer->write('log', Logger::WARNING, 'test3');
         fseek($handle, 0);
         $this->assertEquals('testtest2test3', fread($handle, 100));
     }