Thanks for the advice! No problem for that, at this time, I'm not on the futur production server.
One word of advice though, think twice before going from "test phase" to "production phase" with the same install, if the default domain you installed your test Zimbra with is not your true default domian. It does create a few small annoyances that will need to be delt with. I built a test zimbra server back in October and used a test.domain during the build and I do regret, from time to time, massaging that one into a prod machine rather than starting with a fresh build once I decided to keep Zimbra.
Request is done. Will this feature be added in 3.2 release ?
Today you can only have one default domain for IMAP (and POP, etc). For the web client we can use a virtual host like domain1.host.com and domain2.host.com to allow multiple domains to act as if they are the default. It's likely we could do something similar for IMAP/POP in the future.. Please file this request in bugzilla.