Mousetrap:  Well, you have basically two options.  One is to insist the problem is on the server side and never get your icon uploaded.  Or, you can try to solve it on your side.  Try re-saving the file in one of the other accepted formats (e.g. gif) and uploading that file.  Or convert it to another kind of .jpg (e.g. by changing the level of compression, size, etc.) and make sure it is re-saved as a jpg before uploading.