How do I install PostgreSQL ODBC Drivers for Windows from Source?

I need to test ODBC access to PostgreSQL from Windows clients. Since
the latest binary distribution (postdrv.exe version 6.50.0) seems to be
password protected, and nobody seems to know the password, I downloaded
the source. Everything compiled fine in Visual C++ 6.0, and I now have
a psglodbc.dll file.

What do I do with it? The PSQLODBC FAQ (at
http://404627944:81/post_down/odbc/psqlodbc_faq.html) says to copy the
file into c:\windows\system, but this is apparently insufficient, as the
driver doesn't show up in the drivers list under the ODBC Data Sources
section of Control Panel.

Has anyone here installed this driver from source? How do you do it?
How do we go about getting these instructions into the documentation?

Thank you very much in advance.

Sincerely,
-David Zoll, Programmer
NYSCUL

PS: If anyone has the password to actually run postdrv.exe, that would
be very much appreciated as well.