How can we restrict the user for not allowing the space and '&' in display name while creating the group in FIM portal

Hello All,

While creating group user are entering space and '&' in display name,How can we restrict the user for not allowing the space and '&' in display name while creating the group in FIM portal. Is something need to be change in RCDC? Kindly help.

Regards,
Anirban Singha(India)