Thanks for responding!
When i reinstall i delete all files, blow away the database and start over from scratch.
After some debugging I have come up with the following problem. DB queries return no data!
I have no clue why this might be, as the user has been granted all permissions to the database, and populated the database just fine during the installation... but all of a sudden it cannot read the database?
from class.staff.php:
$res=db_query($sql);
if(!$res || !db_num_rows($res))
return NULL;
$row=db_fetch_array($res);
The login process fails here. despite a properly formated SQL statement, the query returns 0 rows, and the row that is returned has nothing in it. Total mystery to me... As I said, I can get it working fine on other servers, but I need to have this particular installation installed on the one with the problem (as the case always seems to be!)