Column level security in WebI

Hi,

I have a requirement in WebI to hide a measure column values for few groups. I tried the creating Business Security Profile in IDT (with access denied for the measure object) and assigned against the group but when user from that group try to refresh the WebI it give an error. "Some objects are not available to your user profile".

Please let me know if there are any options to achieve this requirement.

Thanks,

Karthik K