what file type is it? and can you explain the upload/redirection process your using to use said avatar ?

I host mine on photo bucket and then I use the Http link from photobucket and the image link from this site and it seems to work for me.

by the looks of it you have too much coding, just put in the http:// without the "[URL" at the front and at the rear of the coding if its there, see how that goes

I put this into the url box

http://i708.photobucket.com/albums/ww86/V-Dubber_photos/1971vw1concept.jpg 

thats my avatar

no worries, sorry it doesnt work for you, works for me though Hope you get it sorted