Need a file converted the right way

Alright, here’s the skinny.
str[e]ak made me this kickass avatar. Here it is.

The problem is, it was saved as a JPEG, and it needs to be a GIF in order for the avatar to work.
I’ve tried using my very limited knowledge of image conversion to fix this, but I can’t do it, it seems, without saving only one frame of animation. So I turn to the Mishmash crew. Hook a fool up?
Got it worked out.
This thread sucks.

And closed.