I have a two drupal sites in mysql server, lets say xyz1 and xyz2.
I have login system through Securesite module to xyz1 and xyz2
Right now users need to put login id and password two times.

How can I login to the system so that users need to put login id and password only one time to browse the xyz1 and xyz2 site
I mean using ONE login id and password(whatever users put it on xyz1 site or xyz2 site) how could I access both sites.
Thanks.