Custom Playermodel Help

Hello I host a roleplay server with custom jobs ect. I manged to get 3 custom jobs working and all that fun stuff. I added a model for the thief class, it downloaded but no one can see it. If the model was not there it would be an error but it is just blank. Hitting F4 and going to the class shows just a blank box which is very strange. I tried deleting the playericon and re-downlaoding it with no sucess. Any ideas? I also use fastdl if that makes any difference.