The image tracking URL is not valid XHTML and "&id" is assumed to be an entity and also it is used in XHTML (such as a div id). This is causing me many issues. May I suggest escaping all instances of '&' into '&' to be inline with XHTML standards?
This will fix W3 validation errors (both my main web site and SMF forums), could fix the template errors, and maybe more.

<img src="hxxp://example.com/index.php?action=adpro;sa=v&id=3&l=1000&m=0&t=1265098566" alt="" />
BV EDIT: removed the bolding tags in the line above.