If you're trying to use pam_pgsql 1.0 and keep getting this message:

PAM_pgsql[652]: the database, table and user_column options are required.

The problem is that the message is an outright lie. Those columns don't exist anymore in 1.0. What it really means to say is:

the connectionstring, getpassword, and changepw options are required.

Apparently there was a renaming at some point but someone failed to update the error message. This can be really confusing as there's a lot of conflicting information on the web. In short, the README is correct, but fails to note which fields are required (I was omitting changepw as I didn't need it).

I'd love to report this bug as it wasted a fair amount of my time and ultimately required that I finally read the source code to figure it out (not too bad, it's only a small C file), but unfortunately the authors are undocumented as well.