Image manipulation in PHP

Apologies in advance if this is a repost, my original message was held up while awaiting confirmation of my e-mail addy and such and I haven't seen it appear yet. Is there any support for TGA images in PHP. I have been writing some code to upload files, convert them to JPG and create thumbnails. Everything works correctly when using JPG's and BMP's as the source files however I would also like to be able to support TGA's. (The idea behind this is enable people to upload screenshots from various games without having to convert them to JPG first as my code will do it for you) I have searched through the PHP manual and through the GD library website and cannot even find a reference to TGA, is there no support for TGA images in PHP at all? (this seems rather strange as TGA is quite a commonly used GFX format) Can anybody help?