Login via windows application? (C#)

[Craigomatic]

I have a C# windows app that I want to allow to login to vBulletin. I figured there are 2 options:

1. Create a php page that the app posts the username and password to which outputs true or false on an attempted login.

2. Connect directly to the vBulletin database from my application and rewrite the login function from the login include directory.

I have tried to do option 1 by writing a php page that essentially is very similar to the login.php file that comes with vBulletin.

My problem is that im not sure how to get vb_login_md5password and vb_login_md5password_utf in the code sample below and im not sure how to correctly hash the password...I assume that method wants a hashed password?

PHP Code:

//$usr and $pass are post variables from my windows app 

if (!verify_authentication($vbulletin->GPC[$usr], $vbulletin->GPC['$pass'], $vbulletin->GPC['vb_login_md5password'], $vbulletin->GPC['vb_login_md5password_utf'], $vbulletin->GPC['cookieuser'], true))
    { 


Any help/comments appreciated!