connecting using User alias ?

Hello,

Our portal use a backend sap system to get the user authentification/authorization. User in this systems are created with username, password lastname, firstname, and alias, by the way of a call to BAPI_USER_CREATE1 (from another sap system).

Since we use the SAP login, we are restricted to 12 characters for the login. We thus would like to use the alias instead in the portal.

Is this possible ?

Regards,

Guillaume PATRY