GD & PHP 3.0 Series
Just a small info:
PHP 3.0 series by default does have GD support. For dummies: GD is the library with the help of which dynamic images are created in PHP. GD in PHP 3.0 series does not have gif file support.
I once read that latest versions in PHP 4.4 series have default support for GIF files. have not yet tested it my self.