Login with user alias possible via SAP GUI?

Question: We are investigating possibilities to convert all our R/3 userids. This is to enable future SSO via SAP Portal.
Problem however is that the future userid comes from a central identity repository and is not really end user friendly. It is a 9 digit number and if in anyway possible, we would like to use the friendly name that people will use to login to the portal. This is typically the combination of first name and family name and will most likely be longer than 12 characters.
Since we will continue to use SAP GUI for some time, it would be nice if there are possibilities to use the user internet alias for login to SAP.
Any suggestions?

Answer:
We are ECC5, th elast sentence in the Help for Internet Aliases says

"At the moment, you cannot use alias names for SAP GUI and RFC logons to the system."

This may be an indicatino tha tit will be available in the future, or (more cynically) they haven't figured out how to do it yet.
_________________