Exporting local mail out of Zimbra Desktop for use in another app

[tommmyboy]

In order to adopt Zimbra Desktop, I must have a way to be able to get any POP messages that are downloaded off the server and saved locally in Zimbra to be exported for use in another, non-Zimbra desktop email client should I ever need to do so. Is this possible, and if so, what format is produced by such an export?

I've searched quite thoroughly about exporting mail out Zimbra and there are a number of references to a resulting zip file, but I cannot find any information on what format this export produces or whether or not it can imported into different email app.

The only references I was able to find talk about re-importing exported mail back into Zimbra.

There is this: [SOLVED] Is there a .pst like function available? where the poster makes reference to the export being a standards-compliant format. But doesn't say what format that is.

Thanks in advance.