diff --git a/include/actionlib/client/action_client.h b/include/actionlib/client/action_client.h
index 00a3ad10..5d02e482 100644
--- a/include/actionlib/client/action_client.h
+++ b/include/actionlib/client/action_client.h
@@ -165,6 +165,10 @@ class ActionClient
    */
   bool waitForActionServerToStart(const ros::Duration& timeout = ros::Duration(0,0) )
   {
+    // if ros::Time::isSimTime(), then wait for it to become valid
+    if(!ros::Time::waitForValid(ros::WallDuration(timeout.sec, timeout.nsec)))
+        return false;
+    
     if (connection_monitor_)
       return connection_monitor_->waitForActionServerToStart(timeout, n_);
     else