"Logging" a user onto Gallery in advance ?

Have only just installed Gallery 1.5 but was wondering if anyone more familiar with its workings could help me with something.

I'm in the process of making my own sort of content management system written in php and what I want to be able to do is have one basic log-on and then not require the user to have to re-logon to any of the other systems that my site will be linked to. I've managed to do this with the message board that I use but was also wanting to do the same thing with Gallery. In other words what routines would I need to run (in PHP) in order that when a user clicks on a link to use Gallery they are already logged on without having to click the login button/text in Gallery itself and fill out their details. I had a brief look at the code and I'm assuming that some session variables would need to be set but it would save me a huge amount of time if someone more knowledgable with the product could point me in the right direction.

Thanks in advance,

Ian

Have followed the link you posted but didn't mnage to find a solution. Another poster is also having the same problem:

http://gallery.menalto.com/index.php?name=PNphpBB2&file=viewtopic&t=28412

Basically, I just need the bit of code from the gallery application that I can run in my own PHP program which will automaticaly log users on to Gallery without them having to re-enter their logon details again when they choose the Gallery link from my "portal". I have tried taking bits from Login.php but can't seem to get it to work. Can anyone help please?