I am wondering if it is possible to use just the WebMail server with existing mail servers (ie: custom/legacy e-mail servers, or even just M$ Exchange Server [without the zimbra colaboration server in between]).

I am presuming that this is not a drag-and-drop solution, that it would need a LOT of re-working, to use JUST the webMail server (essentially the pages that serve up the e-mail inbox interface to the client side) and have it talk to an existing/legacy e-mail server/system.

It seems like the webMail server is all/mostly Java/Tomcat, so a couple of questions here. Can the webMail server be installed on a different machine than the Zimbra Collaboration Suite? To further that question, can the webMail server be installed on an M$ box (with Tomcat) and be set up to talk to an existing/legacy e-mail server system ... either on M$ or Linux.

Essentially, we are interested in the webMail interface, but would like to incorporate this into an existing/legacy e-mail system. Can this be done, and if so, how much work would it take to get this done (presuming that we have competent java developers to throw at this)?