[Dspace-general] user registration problem

[esperi]

Hello,

We've been having some problems when a user is trying to register with our 
DSpace (1.2) system. The user would get an Internal System Error message 
after entering his/her email address followed by clicking on Register 
button. Only the first user can be registered after restarting the system.

Any help or suggestion would be appreciated,

Thanks,

Yiqun