Orignial file:

echo "<a href=\"$url\"  onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('add2cart','','images/cart_over.gif',1)      >";

Changed to to escape ' and " :

echo "<a href=\"$url\" onMouseOut=\"MM_swapImgRestore()\" onMouseOver=\"MM_swapImage(\'add2cart\',\'\',\'images\/cart_over.gif\',1)>\";

Is this correct?