Ubuntu :: Picture Associated With Account

I installed 10.04 on a lappie the other day, and it all works nicely! BUT, there is also XP on another partition of the hard drive, and the Ubuntu install has taken some properties from the XP accounts on there. One of the properties it has taken is a picture associated with my account. (You know the thing, XP has them built-in. A cat looking through a mousehole, a kid on a bicycle, a chess board etc etc etc). And I can't remove it. System > Administration > Users and Groups shows me a list of all the accounts, and the picture associated with my account, but it doesn't have any method of removing the picture (or of associating a picture with any other account, come to mention it.)

I could create a new Ubuntu account without the picture but that would involve swapping settings between the accounts, which would be a pain.