Restricting Sender Identities

[Hakke]

Hello,

we are using RoundCube Version 1.0.1.

We are already using virtuser Plugin to set up the right identity on startup because we use different domains (subdomain1.domain.com, subdomain2.domain.com and so on... )

Is there a possibility to restrict user identities like they can only add maildomains which are already exists because of their startup configuration like only subdomain1.domain.com??

If there is no possibility: How can i define a special domain for adding identities like *.domain.com ?

thanks for your help!

Hakke