mac 10.4.x and logging into windows active directory

whenever one of my users turns on her imac, and tries to log on to our windows servers domain, the logon window shakes and doesn't let her log in. but when you use a local mac logon and log in locally, then log out and then try to use your domain login, it works. why does it do that? it won't let you log into the windows domain when you first turn on the computer, but will after you logged in to a local computer then log out. so now she doesn't turn her computer off at nights. does anyone else have this problem? this is mac os x 10.4.x tiger.

 

hello... we have to wait about 30 minutes before it lets us log in... the logon screen appears immediately. just that it won't let us log in until we wait over 30 minutes.