building PHP Apache module with PostgreSQL support

Hello everyone!

I sucessfully installed Cygwin with Apache 1.3.24-5 and PostgreSQL 7.2.1-2
running as NT services on my WinXP machine. After this I wanted to check out
phpPgAdmin to play around with.
I installed the mod_php4 (4.2.0-1) package and modified Apache's httpd.conf
file but was not able to start Apache properly:
API module structure 'php4_module' in file
/usr/local/apache/libexec/libphp4.dll is garbled - perhaps this is not an
Apache module DSO?

However, I think the precompiled mod_php4 bins doesn't support PostgreSQL
and downloaded the sources (apache-php-4.2.0-1-src.tar.bz2). I configured
PHP with the required options (after the steps described in
php-4.2.0-1.README):
./configure --with-apxs --without-mysql --with-pgsql

This process terminates with:
...
checking for PostgreSQL support... yes
configure: error: Cannot find libpq.so. Please specify correct PostgreSQL
installation path

Of course there are no *.so files available under Cygwin. Is there a patch
to fix that, or under which topic I should search  for in the mailing list?

All packages are installed with Cygwin's setup.exe. Additionally the sources
of Apache and PostgreSQL are hosted in:
/usr/src/apache_1.3.24-5
/usr/src/postgresql-7.2.1-2

Then I decided to build PHP without pgsql support to find out if this will
run smooth. Unfortunately, a problem appeared during the installation
described below. I followed the steps pointed out in php-4.2.0-1.README that
are:

  tar xjvf apache-php-X-Y-src.tar.bz2            [1]
  patch -p0 < php-X-Y/CYGWIN-PATCHES/php-X-Y.patch    [2]
  cd php-X-Y                            [3]
  autoconf                                [4]
  ./configure --with-apxs                    [5]
  make                                [6]
  cd sapi/apache/.libs                        [7]
  ../../../CYGIN-PATCHES/mkdll.sh libsapi.la \
    -L ../../../.libs -lphp4 \
    /usr/bin/cyghttpd.dll                    [8]
  mv cygsapi.dll libphp4.dll                    [9]
  /usr/sbin/apxs -i -a -n php4 libphp4.dll          [10]

The process of creating the cygsapi.dll [8] stopps after a list of
"undefined reference to..." messages with following error:
collect2: ld returned 1 exit status

It would be great if someone could give me a hint in order to bring the PHP
module with pgsql support up and running .

Are there any further steps necessary for the combination
Apache/PHP/PostgreSQL under Cygwin?

Thank you in advance!
Regards, Andreas