OK. So you've gotten quite a few answers on this, but I want to iterate what I've done to compile this module. I prefer not to set these environment variables in my .*rc or .*_profile files for the simple fact that once I'm done with this compile I won't be using them again.

With RH7.0 I assume you're using BASH, so you'd simply do the following at the command prompt:

export POSTGRES_LIB="/usr/local/pgsql/lib/"
export POSTGRES_INCLUDE="/usr/local/pgsql/include/"
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or whatever the correct path is. If you installed the RPM for pgsql-dev, then they might just be in /usr/lib and /usr/include somewhere.

If you really feel the need to include these in your .*rc or .*_profile files, you don't need to log out to activate the changes. Just execute the files. They're shell scripts, and the express purpose of a shell script is to be executed from a shell. Use either sh .bashrc or ./.bashrc depending on whether your .bashrc is set to be executable or (probably) not.

It doesn't matter what user you are when you run configure, make and test as long as you have write permissions to the folder the module source is in, but you need to be root to install the module in a system-wide-available fashion (recommended).