How do you add gifs as your AIM buddy icon?

when you select ';upload a picture';, it says the supported picture formats are JPG, GIF, BMP, or PNG. Everytime I select a GIF file as my picture though, it doesn't move once installed as my buddy icon...but when I open it normally in the folder it was saved in on my computer, it moves. What am I doing wrong or how do I change my picture to a GIF correctly?How do you add gifs as your AIM buddy icon?
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