MING can be tricky to install, but it can be done. Tell your ISP admin to check out Running SWF with Ming if he has trouble.

In case you want to go with pure Perl, SWF::File has an img2swf.plx and jpeg2swf.plx scripts in it's samples directory. They work, and they are pure perl, so you could use them in your home dir. The img2swf script uses Image Magick to convert formats.