undefined reference to `ECPGconnect'

Hi all,
I haven't been able to figure out why I'm receiving this error. Can someone
help me out? It may be worth noting that in the generated file (after
preprocessing), I had to modify the prepended #include's to have 'pgsql' in
them (ie. #include <pgsql/ecpgtype.h>).
Thanks for any help!
Mark

$ gcc -I/usr/include/pgsql manager.c -o manager
/tmp/ccU8a5E9.o: In function `parser':
/tmp/ccU8a5E9.o(.text+0x197): undefined reference to `ECPGconnect'
/tmp/ccU8a5E9.o(.text+0x1af): undefined reference to `ECPGdo'
collect2: ld returned 1 exit status