Here is a short script that makes my httpd crash about 1/3 of the time.  Reduce the number of httpd server processes to 1 or 2 or you may have to execute it many times before it starts crashing.

Correct output: several hundred lines of "A reasonably long string..." mostly separated by blank lines.

Observed output about 1/3 of the time: an EOF before any status message returned.

<script language="php">
  // Alter connect line to match a database of yours
  $connect_str = "host=... dbname=tv user=webadmin...";
  $c = pg_connect($connect_str);

  for ($i = 0; $i < 20; $i++) {
    $array[$i] = "A reasonably long string to make sure that allocations happen $i<br>\n";
  }

  // Trigger some NOTICE messages, allocate storage in between
  $big = '';
  for ($i = 0; $i < 20; $i++) {
    // This triggers a NOTICE message about the primary key
    $rc = pg_exec($c, "create table testing ( c int4 primary key )");
    // drop table for next iteration
    $rc = pg_exec($c, "drop table testing");
    // close connection, triggering efree(last_notice)
    pg_close($c);
    // reconnect
    $c = pg_connect($connect_str);
    // do something to allocate lots of storage
    $big .= join("\n", $array);
  }

  // use the allocated storage
  print "$big\n";

</script>


Configuration: Apache 1.3.20 on Linux RH 6.2 or 7.1 (this script "works" on both).  PostgreSQL 7.1.3.  PHP configured with: 
 './configure' '--prefix=/usr' '--with-apxs' '--libdir=/usr/lib/php4' '--includedir=/usr/include' '--datadir=/usr/share/php' '--with-config-file-path=/etc' '--enable-inline-optimization' '--enable-magic-quotes' '--enable-track-vars' '--enable-memory-limit' '--enable-bcmath' '--with-gdbm' '--with-xml' '--with-expat-dir=/usr' '--with-mm' '--with-openssl' '--with-gd=shared,/usr' '--enable-sysvsem=shared' '--enable-sysvshm=shared' '--enable-shmop=shared' '--with-gettext=shared' '--with-pspell=shared' '--enable-sockets=shared' '--enable-wddx' '--enable-apc=shared' '--with-zlib=/usr'

This is fixed in CVS. Try the latest CVS snapshot from 
http://snaps.php.net/ to verify it. Reopen if it doesn't
work. 

--Jani