diff -u b/core/modules/simpletest/tests/theme.test b/core/modules/simpletest/tests/theme.test
--- b/core/modules/simpletest/tests/theme.test
+++ b/core/modules/simpletest/tests/theme.test
@@ -121,7 +121,6 @@
     $this->assertIdentical(theme('theme_test_foo', array('foo' => 'a')), 'a', t('The theme registry contains theme_test_foo.'));
 
     module_disable(array('theme_test'), FALSE);
-    $this->assertIdentical(theme('theme_test_foo', array('foo' => 'b')), '');
     $this->assertIdentical(theme('theme_test_foo', array('foo' => 'b')), '', t('The theme registry does not contain theme_test_foo, because the module is disabled.'));
 
     module_enable(array('theme_test'), FALSE);