send portal notification instead of email notification

Hello,

I am working on ep6 sp2. Currently, evey time a new member is added into a collaboration room (SAP standard template)an email is sent to inform the user about the invitation. I have a reqirement to send notification like the subscription notification instead of an email

notification. so that the user does'nt have to check his email but can just see the notification in the recent notification window. is this possible? I'd appriciate any kind of help.

thanks

-smitha