Well he said his signature gets changed automaticly every day, not something like what I have right now (random image). Check the name of the image he has in his sig, it's one.jpg, two.jpg, etc.
EDIT: oh silly me, it's a header() forward function

. *slaps face* I didn't know forums would accept that method, that's why I used the method to actually let the browser think the php page is the image

.
Same as with this one below (decided not to use it just yet

):
