Comment 5 for bug 432291

I can reproduce this bug.

php -v

PHP 5.2.10-2ubuntu4 with Suhosin-Patch 0.9.7 (cli) (built: Sep 18 2009 15:43:11)
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2009 Zend Technologies

cat t.php

<?php
$fp = gzopen("file.gz", "r");
?>

php t.php

Fatal error: Call to undefined function gzopen()

From package description:
The following extensions are built in: ... zlib.

uname :
2.6.31-11-generic #38-Ubuntu SMP Fri Oct 2 11:55:55 UTC 2009 i686 GNU/Linux