Issue backing up multiple time machines...(not lion related)

[spaztic1]

I am playing with freenas and trying to get a mac mini and a macbookpro to back up to the same external hard drive using freenas8. I can get them both to see the hard drive but I cant get them both to back up. One will start backing up and the other says "two of the disks to be backed up have the same name. Please rename one of them." I tried creating a new AFP share (one for each mac) and that didnt work.