Getting into a loop if entered a wrong password

[Sirius]

OS: Windows 2000
Centred Version: 0.4.1

Description:
After entering a wrong password centred tells me that my password is incorrect, after clicking "OK" it gets into a kind of loop. The only thing I can see is the authenticating-window (see attached JPG). To close this I have to kill it with the process-manager.

Edit: Same Problem if an account is blocked and tried to log in