I dunno if there's a mod for this, but I doubt it

now what I think about is that when ppl sign up to the forums they have an pre-set avatar that has been chosen for all new sign ups by the amdin, so even before changing anything in their avatar options they have that avatar, it could be like a site logo the forums are affiliated with...
and additional the admin could chose a number of post or member group a member has to have achieved before changing his avatar to one of the gallerys or a custom one...

what you think?

I like the idea...I would think it would be a relatively easy mod, somewhere in the script that creates a new user account, to set the avatar value to a certain file?

^^yeah, I just found a mod tutorial to this on invionize forums