TOPIC: Guest default profile picture?

Sorry if this has been asked before.

I just enabled guest posting for the comments on my site. I was wondering if it is possible to enable a default avatar for the guests, that way users know they are guests. I am also integrated with JomSocial, just in case that was important.

An example of a guest comment + 2 user comments is at the bottom of this article

Hm that is strange. Do you have gravatar enabled?
I think that if you enable gravar you will see the image for guest users.

Nope, no gravatar. Will gravatar interfere with my jomsocial / jfusion / phpbb integration per chance? Thanks for the fast response as always.

It shouldn't - if the user has a jomsocial avatar - then this avatar will be loaded. If it hasn't then the system will look for a gravatar, if the user doesn't have one - the guest image will be shown.