Enroll user PGP Desktop with local user

Hi,

I install PGP on environment, and my customer use PGP with internal users.

This users don´t have a valid email address, and when I try to install the PGP Desktop to enroll, I receive a message saying the PDP sent a request enrollment to the e-mail, but this email don´t exist!

Exist any way to bypass this e-mail verification to enroll?

thanks