Jani Hartikainen has made a recent post about a library that can manage PDF generation a bit better than the Zend_PDF component of the Zend Framework - RE_PDF.

Zend_Pdf, while generally quite good, has one big issue: It does not support word wrapping text! There’s a new and still a bit obscure framework called RE Framework, which has an excellent PDF component - it includes support for word wrapping, better support for PDF templates, image loading etc.

The several of the interfaces (method calls) are similar between Zend_Pdf and RE_Pdf, so there's not too much rewriting involved if you're already using Zend's option. He shows how to parse an XML file, plug those values, the fonts and fields, in the PDF object then flesh it out with a presentation layer and information to fill in the blanks.