I have XOOPS 2.2.3 and XoopsGallery 1.3.3.7 in my server. When I try to upload a pic, I get this error message. "Error: unable to make thumbnail (0) !

The site says I have pictures in there, but I can't see them. I don't know what is going on. I also tried XoopsGallery 1.3.3.6 and get the same thing. I just tried XoopsGallery 1.3.3.8_Test1 and I get the same thing. My PHP Version is 4.4.0 MySQL Version is 4.0.25-standard.