controlled files to be deployed to different environments

[Daniels, Dave F]

For one of my projects I have a configuration file, say mail.properties,
which I'm versioning in CVS. The contents of this file will be different for
different environments, though. For example, the mail server for my
development environment is different than for my production environment.

Currently, I have the development version controlled, and when my project is
ready for deployment to production, I manually change the contents and send
it off (but don't change the version in CVS). I would like suggestions on
ways to control different versions of the same file. So far, the best idea
we've come up with is to give each version a different extension and then
use our make utility to pull the right one and rename it, so
email.properties.dev becomes email.properties. Any other suggestions?

Thanks,
Dave