using global.php from non-vb page

[rsjpp]

I have a custom application in which I want to make use of VB's user authentication.

I tried including global.php and checking for bbusrinfo[userid] variable etc..

But since vBulletin is using includes like below
("./includes/xxx.php")
the scripts in nonVb folders are failing in includes...
Had vBulletin used ("includes/xxx.php") without the preceding "." for current directory, it would have worked.

Can you help me how I can check if a user is already logged in from my custom script?

Thanks