Not really. SRV records could allow this, but IE does not query for SRV
records, it queries for A records. You could probably redirect
webmail.mydomain.com to that uri including the port number on a web server
however using redirects.
Not in DNS. You can do it on your webserver. You create a website called
"xxx.xxx.xxx.xxx", you bind it to port 9998. You create a webiste called
"webmail.mydomain.com", you put a default page in there that redirects to
xxx.xxx.xxx.xxx:9998
--
Sincerely,
Dèjì Akómöláfé, MCSE MCSA MCP+I www.akomolafe.com www.iyaburo.com
Do you now realize that Today is the Tomorrow you were worried about
Yesterday? -anon