[ODBC] compiling odbc

I am attempting to compile and install psqlodbc-08.03.0200 on my Mac Pro running Leopard.

Here is what I get:

client-66-xxx-17-x14:psqlodbc-08.03.0200 brent1a$ sudo ./configure

checking for a BSD-compatible install... /usr/bin/install -c

checking whether build environment is sane... yes

checking for gawk... no

checking for mawk... no

checking for nawk... no

checking for awk... awk

checking whether make sets $(MAKE)... yes

checking whether to enable maintainer-specific portions of Makefiles... no

checking for pg_config... no

configure: error: pg_config not found (set PG_CONFIG environment variable)

How do I fix "configure: error: pg_config not found (set PG_CONFIG environment variable)"

(I'm relatively new to most of this?

thanks

-B