Lotus Notes account diabled by Blackberr

I have installed Blackberry software from nextel on a PC. After signing on to Desktop Manager with the user’s Lotus Notes account, I receive the message “Your Notes account has been disabled by you Blackberry administrator. Do you wish to select another account?”. We have checked the server and the account is not disabled. In addition, when trying someone else’s Notes ID that has a blackberry, I have no problem and do not get any error message. Does anyone know what could be causing this?