curious: iphone compiling?

I'm curious regarding stuff like Chmox -- I've been able to install the Installer.app and a lot 3rd party software - including Ruby, Stumbler, etc. What I'd REALLY like is 2 viewers for a lot of the digital manuals I've got - a good PDF reader, and .chm viewer. Though I've tried the Preview.app, it doesn't work for the pdfs I have - but emailing them to myself does. Now, if there's a way of compiling Chmox for the iphone that would rock. On a different note - how does one add to the $PATH in z-shell?