<?php echo "<a href=\"javascript://\" onClick=\"document.getElementById('footerSlideContainer').style.display ='block'\" > <img src='Dealer/images/email_send.png' style='width:22px;height:22px' /> Contact Advertiser </a>"; ?>
try this code. problem is your javascript code in onClick event. what you want to do?
document.getElementById('footerSlideContainer').style.display ='block';
or
clearChildren(document.getElementById('row11'));
If you want 1st one copy my code, else there is nothing wrong with your code. That means bug on clearChildren(), check clearChildren() is defined and works perfectly.