Ok, this one took me ages to track down.

On IIS running PHP 5.2.8 (also believe the problem exists when using 5.2.2) with FastCGI or ISAPI Module... using the following causes Zend Framework to miss the Location header:

header('Location:http://www.google.com/'); exit();

The above will work when served from an Apache PHP server but not on IIS 6/PHP. The following quick fix will solve it:

header('Location: http://www.google.com/'); exit();

(Note the space)

I would suggest the following fix. In Http/Response.php line 500 of the extract header function, replace:

if (preg_match("|^([\w-]+):\s+(.+)|", $line, $m)) {

With:

if (preg_match("|^([\w-]+):\s*(.+)|", $line, $m)) {

(Making the space optional)

Thanks Tom