diff --git modules/color/color.install modules/color/color.install
index 4bb3e4c..33515c5 100644
--- modules/color/color.install
+++ modules/color/color.install
@@ -18,12 +18,12 @@ function color_requirements($phase) {
       );
 
       // Check for PNG support.
-      if (function_exists('imagecreatefrompng')) {
+      if (function_exists('imagecreatefrompng') && function_exists('imagefilter') && function_exists('imagerotate')) {
         $requirements['gd']['severity'] = REQUIREMENT_OK;
       }
       else {
         $requirements['gd']['severity'] = REQUIREMENT_ERROR;
-        $requirements['gd']['description'] = t('The GD library for PHP is enabled, but was compiled without PNG support. Check the <a href="@url">PHP image documentation</a> for information on how to correct this.', array('@url' => 'http://www.php.net/manual/ref.image.php'));
+        $requirements['gd']['description'] = t('The GD library for PHP is enabled, but does not support some features that Drupal requires. Check the <a href="@url">PHP image documentation</a> for information on how to correct this.', array('@url' => 'http://www.php.net/manual/ref.image.php'));
       }
     }
     else {