I don't see any ads, but I don't see any signatures on any of you either
Hardly any ads get past Firefox and AdBlock Plus.
Anyway, here's how mine is done.
No spaces between tags, and no caps in tags, and remember to close the tag with a / on the last one.
Also, the following profile options are all set to YES (the html isn't important, but it doesn't hurt):
Code:
Always attach my signature
Always allow BBCode
Always allow HTML
Hope that helps. ;P
Code:
[img]http://directurl.jpg[/img]