rewrite for webmail

Hi everybody,

I'm looking for a solution for the following problem. There is a server with ISPConfig and about 75 domains on it. Now I want that every user can type in the following url

http://webmail.<mydomain>.<tld>

and see the content from

https://<servername>.<domainname>.<tld>:81/webmail/

I asked google and this forum. I don't want to add a co-domain to every domain. I think there should be a way to this with a rewrite rule.

Any hints?

 

This link might help you: http://httpd.apache.org/docs/2.0/misc/rewriteguide.html