Limiting External Sending per Account

[dmg]

I will be sending people some demo accounts, and I would like them to be able to send email within the domain, but not to any external domains.

The goal is to prevent them from sending mail to external domains using our domain name.

Is this possible to configure for individual accounts?

Thank you,

David

[mmorse]

This will prevent them from emailing the outside:
Restrict sending to certain domains - ZimbraWiki

And if you want to restrict who can send TO the demo accounts:
RestrictPostfixRecipients - ZimbraWiki