diff --git a/src/Phing/Task/System/ExecTask.php b/src/Phing/Task/System/ExecTask.php
index 6f3178d2f..1914811ae 100644
--- a/src/Phing/Task/System/ExecTask.php
+++ b/src/Phing/Task/System/ExecTask.php
@@ -469,6 +469,8 @@ protected function prepare()
      */
     protected function buildCommand()
     {
+        $this->realCommand = '';
+
         if (null !== $this->error) {
             $this->realCommand .= ' 2> ' . escapeshellarg($this->error->getPath());
             $this->log(