diff --git a/src/ClassAliasLoader.php b/src/ClassAliasLoader.php
index 24be55c..95077e9 100644
--- a/src/ClassAliasLoader.php
+++ b/src/ClassAliasLoader.php
@@ -98,7 +98,7 @@ public function getClassNameForAlias($aliasOrClassName)
      */
     public function register($prepend = false)
     {
-        $this->composerClassLoader->unregister();
+        spl_autoload_unregister(array($this->composerClassLoader, 'loadClass'));
         spl_autoload_register(array($this, 'loadClassWithAlias'), true, $prepend);
     }
 
diff --git a/tests/Unit/ClassAliasLoaderTest.php b/tests/Unit/ClassAliasLoaderTest.php
index e27ba9c..bc8d5c6 100644
--- a/tests/Unit/ClassAliasLoaderTest.php
+++ b/tests/Unit/ClassAliasLoaderTest.php
@@ -46,15 +46,6 @@ public function tearMeDown()
         $this->subject->unregister();
     }
 
-    /**
-     * @test
-     */
-    public function registeringTheAliasLoaderUnregistersComposerClassLoader()
-    {
-        $this->composerClassLoaderMock->expects($this->once())->method('unregister');
-        $this->subject->register();
-    }
-
     /**
      * @test
      */