How to add files dynamically to an already existing rpm ?

[ancest]

Hai friends,
I am facing a problem. I want to know how to add files to an already existing rpm. Not at the creation time of rpm. Because we have to add some files to it dynamically if any user purchases it from our webserver. I have searched everywhere but havent find any. Is it possible to do so?

Any help will be deeply appreciated.

[bigtomrodney]

I know it's possible to open an rpm file as if it were a normal archive using cpio/gzip but I think you'd have to have the files mentioned in the spec file for the rpm. This might not matter if you're replacing a file with one of the same name, but I'd hazard a guess that you'd be better off having their rpm dynamically built for them each time.