Linking problems

I wrote a trivial (so I didn't include, but I will if I must...) C
program using the libpq C interface which compiles cleanly. My problem
is with the linker. There are two files, one contains (tested) code
for a standard set of cgi functions and the other contains code that
calls the db. Here's the gcc command I'm using:

gcc login.c stdcgi.c -I /usr/local/pgsql/include/ -L
/usr/local/pgsql/lib/ -lpq

And here's the error I'm getting:

/usr/local/pgsql/lib//libpq.a(fe-auth.o): In function
`pg_password_sendauth':
fe-auth.o(.text+0x17): undefined reference to `crypt'

I haven't dug through the postgreSQL code and perhaps I haven't read the
user manual thoroughly enough, but I'm not making any calls to
"pg_password_sendauth", so I'm confused with this error message.

Any help would be appreciated.

Randy Barrett
rbarr(at)shadow(dot)net