There is no complaint from UBB when I insert the HTML, and none from UBB when I view the page.
The result is:
1. It's simply blank where the ads should be
2. IE status bar shows "Done, but errors on page"
When you double click the IE error Icon, you get a popup desctibing the error.
Please try it and tell me what you think:
http://www.game-master.net/cgi-bin/ultimatebb.cgi
