diff --git a/src/Composer/Autoload/AutoloadGenerator.php b/src/Composer/Autoload/AutoloadGenerator.php
index 8f8aa87d8..636f3f448 100644
--- a/src/Composer/Autoload/AutoloadGenerator.php
+++ b/src/Composer/Autoload/AutoloadGenerator.php
@@ -145,6 +145,8 @@ EOF;
                 $classMap[$class] = '$baseDir . '.var_export($path, true).",\n";
             }
         }
+
+        ksort($classMap);
         foreach ($classMap as $class => $code) {
             $classmapFile .= '    '.var_export($class, true).' => '.$code;
         }
@@ -198,13 +200,14 @@ EOF;
      */
     public function parseAutoloads(array $packageMap)
     {
-        $psr0 = $this->parseAutoloadsType($packageMap, 'psr-0');
-        krsort($psr0);
-
         $sortedPackageMap = $this->sortPackageMap($packageMap);
+
+        $psr0 = $this->parseAutoloadsType($packageMap, 'psr-0');
         $classmap = $this->parseAutoloadsType($sortedPackageMap, 'classmap');
         $files = $this->parseAutoloadsType($sortedPackageMap, 'files');
 
+        krsort($psr0);
+
         return array('psr-0' => $psr0, 'classmap' => $classmap, 'files' => $files);
     }
 
diff --git a/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
index 51c360dae..626c2db07 100644
--- a/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
+++ b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
@@ -238,9 +238,9 @@ class AutoloadGeneratorTest extends TestCase
         $this->assertTrue(file_exists($this->vendorDir.'/composer/autoload_classmap.php'), "ClassMap file needs to be generated.");
         $this->assertEquals(
             array(
-                'ClassMapFoo' => $this->workingDir.'/composer-test-autoload/a/a/src/a.php',
                 'ClassMapBar' => $this->workingDir.'/composer-test-autoload/b/b/src/b.php',
                 'ClassMapBaz' => $this->workingDir.'/composer-test-autoload/b/b/lib/c.php',
+                'ClassMapFoo' => $this->workingDir.'/composer-test-autoload/a/a/src/a.php',
             ),
             include ($this->vendorDir.'/composer/autoload_classmap.php')
         );
@@ -275,9 +275,9 @@ class AutoloadGeneratorTest extends TestCase
         $this->assertTrue(file_exists($this->vendorDir.'/composer/autoload_classmap.php'), "ClassMap file needs to be generated.");
         $this->assertEquals(
             array(
-                'ClassMapFoo' => $this->workingDir.'/composer-test-autoload/a/a/src/a.php',
                 'ClassMapBar' => $this->workingDir.'/composer-test-autoload/b/b/test.php',
                 'ClassMapBaz' => $this->workingDir.'/composer-test-autoload/c/c/foo/test.php',
+                'ClassMapFoo' => $this->workingDir.'/composer-test-autoload/a/a/src/a.php',
             ),
             include ($this->vendorDir.'/composer/autoload_classmap.php')
         );
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap3.php b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap3.php
index 75c7cd741..9c5136d7f 100644
--- a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap3.php
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap3.php
@@ -6,6 +6,6 @@ $vendorDir = dirname(__DIR__);
 $baseDir = $vendorDir;
 
 return array(
-    'Main\\Foo' => $baseDir . '/src/Main/Foo.php',
     'ClassMapFoo' => $baseDir . '/composersrc/foo.php',
+    'Main\\Foo' => $baseDir . '/src/Main/Foo.php',
 );
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap4.php b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap4.php
index 558c5e048..7ea7c42c7 100644
--- a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap4.php
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap4.php
@@ -6,7 +6,7 @@ $vendorDir = dirname(__DIR__);
 $baseDir = dirname($vendorDir);
 
 return array(
-    'ClassMapFoo' => $baseDir . '/composer-test-autoload/a/a/src/a.php',
     'ClassMapBar' => $baseDir . '/composer-test-autoload/b/b/src/b.php',
     'ClassMapBaz' => $baseDir . '/composer-test-autoload/b/b/lib/c.php',
+    'ClassMapFoo' => $baseDir . '/composer-test-autoload/a/a/src/a.php',
 );
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap5.php b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap5.php
index e3230f953..41c1738bc 100644
--- a/tests/Composer/Test/Autoload/Fixtures/autoload_classmap5.php
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_classmap5.php
@@ -6,7 +6,7 @@ $vendorDir = dirname(__DIR__);
 $baseDir = dirname($vendorDir);
 
 return array(
-    'ClassMapFoo' => $baseDir . '/composer-test-autoload/a/a/src/a.php',
     'ClassMapBar' => $baseDir . '/composer-test-autoload/b/b/test.php',
     'ClassMapBaz' => $baseDir . '/composer-test-autoload/c/c/foo/test.php',
+    'ClassMapFoo' => $baseDir . '/composer-test-autoload/a/a/src/a.php',
 );