Restriction for Email Field

Restriction for Email Field

To Whom It May Concern:

I have created a Data Collection Policy Form (http://creator.zoho.com/cooldev007/form/1/) for the benefit of students of our college. Now, I want to restrict the email field for those people who have Gmail, Yahoo! Mail and Rediffmail ID. Others are not allowed to enter any data on this field. Can you people help me to do that?

Thanks,
Cool Dev
Admin

cooldev007