use a different network error image

index.php

@@ -210,7 +210,7 @@
 			<button id="net-alert" dojoType="dijit.form.Button" style="display : none" disabled="true"
 				title="<?php echo __("Communication problem with server.") ?>">
 			<img
-				src="images/alert.png" />
+				src="images/error.png" />
 			</button>
 
 			<button id="newVersionIcon" dojoType="dijit.form.Button" style="display : none">