DI: User name and password for DI connection(6.2)

Hi

I've just write Add-On for version 6.2 that uses UI and DI. Now, I've got a problem to get user name and password in order to connect with database via DI. I know this problem was solved in 6.5 (single sign-on).Does anybody know a simple(or not) way to do this in 6.2?

Thank you