Having given up on Zimbra Desktop years ago, I want to give it another try. I gave up just after VM purchased the program as none of the Mac versions would run. And it's not going well this time either.

Desktop 7.2.3 GA (Build 11971) / OS X 10.8 Mountain Lion

Zimbra replaces the valid email address in the To: field with my email address.

How do I fix this?