Vista - My scan server account keeps getting locked out..

So we have a Xerox x65 set up in all of our business centers. There is a an
account ono the server called scanuser. Our networking guys cant figure out
why ths account is getting locked out for no reason. Our users scan to
paperport in our environment. We creat a folder for a user on the server,
then they go to the X65, pick theyre folder and scan to it. Well when this
account called scanuser gets locked out. Nobody can scan. Is there anyone out
there that has any input as to why this account is randomly locking out. Our
users do not have to log into the scanner They just find theyre folder on the
templpate and simply chose that as the folder they would like theyre scan job
to go to.