errors when making examples in /src/test/examples

Hi,

I am just trying to make the frontend programs in /src/test/examples
There seems to be some problem with finding the libpq libraries.
make all gives errors:

gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations -I../../../src/interfaces/libpq -I../../../src/include -Wl,-rpath,/local/scratch-1/ww220/postgresql-7.1.3/lib testlibpq.c -o testlibpq
testlibpq.c: In function `exit_nicely':
testlibpq.c:14: warning: implicit declaration of function `exit'
/tmp/ccNom46z.o: In function `exit_nicely':
/tmp/ccNom46z.o(.text+0xa): undefined reference to `PQfinish'
/tmp/ccNom46z.o: In function `main':
/tmp/ccNom46z.o(.text+0x3c): undefined reference to `PQsetdbLogin'
/tmp/ccNom46z.o(.text+0x48): undefined reference to `PQstatus'
/tmp/ccNom46z.o(.text+0x69): undefined reference to `PQerrorMessage'
/tmp/ccNom46z.o(.text+0x99): undefined reference to `PQexec'
/tmp/ccNom46z.o(.text+0xa3): undefined reference to `PQresultStatus'
/tmp/ccNom46z.o(.text+0xc4): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0xd9): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0xe8): undefined reference to `PQexec'
/tmp/ccNom46z.o(.text+0xf2): undefined reference to `PQresultStatus'
/tmp/ccNom46z.o(.text+0x113): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x128): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x137): undefined reference to `PQexec'
/tmp/ccNom46z.o(.text+0x141): undefined reference to `PQresultStatus'
/tmp/ccNom46z.o(.text+0x164): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x17b): undefined reference to `PQnfields'
/tmp/ccNom46z.o(.text+0x192): undefined reference to `PQfname'
/tmp/ccNom46z.o(.text+0x1cf): undefined reference to `PQgetvalue'
/tmp/ccNom46z.o(.text+0x200): undefined reference to `PQntuples'
/tmp/ccNom46z.o(.text+0x210): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x21f): undefined reference to `PQexec'
/tmp/ccNom46z.o(.text+0x229): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x238): undefined reference to `PQexec'
/tmp/ccNom46z.o(.text+0x242): undefined reference to `PQclear'
/tmp/ccNom46z.o(.text+0x24b): undefined reference to `PQfinish'
collect2: ld returned 1 exit status
make: *** [testlibpq] Error 1

Afte searching on the net, I added -lpq but the result is not positive:

gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations -I../../../src/interfaces/libpq -I../../../src/include testlibpq.c -o testlibpq -lpq
testlibpq.c: In function `exit_nicely':
testlibpq.c:14: warning: implicit declaration of function `exit'
/usr/bin/ld: cannot find -lpq
collect2: ld returned 1 exit status

What am I missing here?

Many thanks,

Wei