here's another attempt to help...
go to edit your siggie, click on the mountain icon and copy and paste the following line into the little pop up that comes up:
http://www.intercot.com/discussion/images/smilies/icon_mickey_halloween.gif
it will put in the image tags and it should work.
If you get the red "x", copy and paste that same info into your IE address bar and navigate to that page and you should see the bouncing pumpkin. Hopefully, after you do that, you shouldn't see the red "x" in your siggie anymore. If you still do, I'm out of ideas...you might have to go to the tech board for more help...sorry.