iPhone Pocket Reference

I would like to develop and distribute a small application that makes php function definitions and documentation accessible on iPhones. To do this I would extract portions of the PHP Manual and present them with a simple search function. I would charge a nominal fee for this application. Would doing so infringe on the copyright of the documentation? Would I need to include reference to the authors, the creative commons license and the original source material. Thanks in advance, James James Downie jdownie@gmail.com