pthumb - Remote server refresh

Hi, I am using pthumb to take a jpg file from a remote server and resize it. It works perfectly, but with one big problem for me. The image file from the remote server changes every 10 min but filename remains the same. But pthumb doesn't render the new image cause, I guess, it sees the same filename and so it is using the existing created (the first time) file.

Any solution to this?