The moment I read your second reply, I realised that this could in fact be a problem with permissions, with me running the script from the command line as a different user than the browser would - and the browser might not have write-permission to that directory...

Quick ssh into the server at work, and lo! it works.

++dws for turning my head into the right direction!

--cs

There are nights when the wolves are silent and only the moon howls. - George Carlin