I want to add another secondary domain for student email and would
like to have it on it's own GWIA and Webacc and it's own internet
addressing-- i.e. "@students.xyz.org" instead of "@xyz.org"

I have the domain and po running on it's own OES box and will be
adding a SLES box to host the gwia and webacc. However, I'm not
sure what I need to do as far as setting up the links from the new
domain/po to the primary domain and po or the other secondary, which
hosts GWIA and Webacc for the primary. Any special issues I need to
watch for?