Does it work with PHP 5.2.10 ?

Found out:
It fails if the SERVER_PORT (the "listen" setting in httpd.conf) is anything but 80.

Applies to all versions from 5.2.6 to 5.3.0 (those are the versions I have tested)

Please provide a proper reproducing script we can test with anywhere. 
One that starts with <?php and ends with ?> :)

<?php
	/*
	* A test for session_set_cookie_params and setcookie as mentioned in
	* http://bugs.php.net/bug.php?id=48630
	*/

	$cookiename  = 'cookiename';
	$cookievalue = $_COOKIE[$cookiename] + 1;
	$cookietime  = time() + 3600;
	$path        = '/';
	$domain      = $_SERVER['HTTP_HOST']; // this one includes the port if given (example:127.0.0.1:8080).
	$secure      = false;
	$httponly    = true;	

	session_set_cookie_params(0, $path, $domain, $secure, $httponly);
	setcookie($cookiename, $cookievalue, $cookietime,$path, $domain,$secure, $httponly);

	echo '$_SERVER[SERVER_PORT]: ' . $_SERVER['SERVER_PORT']. '</br></br>';
	echo 'cookie_params:';
	_debug_array(session_get_cookie_params());

	echo 'cookie: ';
	_debug_array($_COOKIE);

	function _debug_array($var = '')
	{
		echo '<pre>';
		print_r($var);
		echo '</pre>';	
	}
?>

Well, you're trying to set domain to something that isn't a domain. 
Please check the manual: http://php.net/setcookie and 
http://curl.haxx.se/rfc/cookie_spec.html and 

Ah - my bad.
Thanks for looking into it.