Vb cookies on none vb page

[HuangA]

hi there;
I am currently coding a small network of sites which I am using a common vbulletin for. Since the sites will be running on different domains, they need their own individual custom made login.php to handle logging in. While the query part is fairly straight forward and easy, I can't seem to figure out how to set the cookies.

I know that in order to keep track of the userid, I need something like:
setcookie("bbuserid", $userid, time()+31536000, "/", ".domain.com");

but how about the password and the other session information? How would I come about getting them to the right format vb recognizes?

Regards,
Andy Huang