--- drush_make.project.inc      2009-11-27 15:02:36.000000000 -0500
+++ drush_make.project.inc.patched      2010-01-13 01:23:54.000000000 -0500
@@ -59,8 +59,13 @@
         if (file_exists($filename)) {
           $patches_txt .= '- ' . $url . "\n";
           drush_shell_exec("mv %s %s", $filename, $project_directory);
-          drush_shell_exec("patch -p0 -d %s < %s/%s", $project_directory, $project_directory, $filename);
-          drush_log($this->name . ' patched with ' . $filename . '.', 'ok');
+          $ret = drush_shell_exec("patch -p0 -d %s < %s/%s", $project_directory, $project_directory, $filename);
+          if ($ret) {
+            drush_log($this->name . ' patched with ' . $filename . '.', 'ok');
+          }
+          else {
+            drush_set_error($this->name . ' patched with ' . $filename . '.', 'FAILED');
+          }
         }
         else {
           drush_set_error('Unable to download ' . $filename . ' from ' . $url . '.');