[Exim] Compiling Exim 4.10 on Debian Woody

I can compile OK with the default options, but I'd like to compile in
postgres query support.

I'm setting the following in Local/Makefile:
    LOOKUP_PGSQL=yes
    LOOKUP_LIBS=-L/usr/local/lib -lpq

but I'm getting the following error when I compile:
    ...
    drtables.o(.data+0x1c8): undefined reference to `pgsql_open'
    drtables.o(.data+0x1d0): undefined reference to `pgsql_find'
    drtables.o(.data+0x1d8): undefined reference to `pgsql_tidy'
    drtables.o(.data+0x1dc): undefined reference to `pgsql_quote'
    collect2: ld returned 1 exit status
    make[1]: *** [exim] Error 1
    make[1]: Leaving directory `/usr/src/exim-4.10/build-Linux-i386'
    make: *** [go] Error 2

I'm fairly sure this is because of this:
    pike:~# ls -la /usr/local/lib
    total 1484
    drwxrwsr-x    3 root     staff        4096 Nov 26 11:07 .
    drwxrwsr-x   12 root     staff        4096 Nov 26 11:07 ..
    -rw-r--r--    1 root     staff     1497434 Nov 26 11:07 libatalk.a
    -rwxr-xr-x    1 root     staff         712 Nov 26 11:07 libatalk.la
    drwxrwsr-x    3 root     staff        4096 Sep 16 09:57 python2.1
ie. there's no mention of postrgres in there.

I've installed all the postgres related dev packages I can find with no
luck.
Any idea what I'm missing?

Luke Pascoe.