Setting up Websphere instances as virtual hosts

I apologize up front if this is not the right place to post this to...
However, I know this list is montiored by some *very* knowledgable folks and
can provide guidance quickly....

We've set up four Websphere 3.5.1 (and HTTP servers) instances for test and
production environments (intranet and internet).  We're using different
ports (80 for intranet production, 8080 for intranet test, etc.)  the
developers will use Turnover eCM to move objects from their PC to the QA
environment, then promote the QA objects to production.  To test in QA, the
developers will point his/her browser to the AS/400 and specify which port
to use (8080 for intranet QA, for example)

I'm wondering if there's a way to set it up so that rather than identify by
port, I can point to environments by url (qa.internet.mydomain.com, for
example).  I have access to our DNS server so I can add aliases as required.
I just don't see how I can access a particular environment without
specifying a port.

I did find a bug in the administrator.  I assume it's already been
identified since I'm a "late adapter" of the technology.  If you click on a
web resource under the virtual host, it does not display the correct virtual
host...

any help would be appeciated....

dan