Forward mail to ISP for certain users

Hello,

We have a client who is currently using Linux/Sendmail. They are using
firtual user tables to map e-mail address from their domain to a ISP pop3
account so their franchise users can have an e-mail address at their
domain without needing an actual mailbox. Example:

user@franchise.com maps to user@comcast.net

The server accepts the e-mail for user@franchise.com then just forwards
it to user@comcast.net. The user checks their ISP pop3 account to
retrieve it. They only have 15 real mailbox acocunts on the server and
over 300 of the virtual maps. We are trying to get them on Groupwise, and
I would like to know if Groupwise can do the same thing in regards to
forwarding off e-mail to an ISP pop3 account without storing it on a
local mailbox.

Thanks