Mac Pro Server OS X 10.7.5 account issues

I am having an issue with an account we have setup for our kids to use. The problem is out of our 200 Macbooks OS X 10.7.2 they have issues logging into the account. It will not accept the password and after a few tries sometimes it goes right on or it doesn't.

It is weird. We initially started having problems with the print server so I have switched the printers to a windows server and are fine now. Am I going to have to do away with the mac server here?