Using Digest Authentication with PHP + Apache

im trying to set up DIGEST authentication using PHP & Apache. I have tried doing this using a script i found on the web which gave me an error as it said the method apache_request_headers() didnt exist, which on reading seems that is becuase apache is not set up to pass the headers to php. I tried installing HTTP_Auth using PEAR, and it fails with this error

Fatal error: Call to undefined function getallheaders()

which upon reading is just the same function, just an alias name.

Is there any other way i can implement digest auth? I would use .htacess config but i want to able to reference the user thats logged in via a database and not sure if i can do it that was using .htacess.

Any ideas, or am i stuffed?

Thanks

Ah, I think the problem is because PHP is installed in CGI mode as opposed to Apache module, so no header access.