zend pdf merge files

[newlasdjfk]

Is anyone familiar with Zend Pdf framework and knows how to use it to merge two pdf-files.

Trying to open and merge 2 pdf-files. Gives me the following error.

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Uncaught exception 'Zend_Pdf_Exception' with message 'Page is attached to one documen, but rendered in context of another
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<?php
require_once 'Zend/Pdf.php';

$pdf1 = Zend_Pdf::load("1.pdf");
$pdf2 = Zend_Pdf::load("2.pdf");

foreach ($pdf2->pages as $page){
$pdf1->pages[] = $page;
}

$pdf1->save('3.pdf');
?>


Might be some lack of understanding of how pages are "attached" to documents. I though it was just an array, containing page-instances.

Any help appreciated immensely!!