Each time you call exec(), you're starting a new process; any changes made to the environment variables in a process will affect only that one process and its own children, not any other process you start with exec().
There are several Runtime.exec() methods; several of them take a String argument called "envp", which lets you pass environment variables to the process you're launching.
I was hoping I wouldn't have to do something like that. I am doing some maintenance on an old, and very poorly designed swing gui. The easiest solution seemed to be to set environment variables for the parent. I guess that may not be possible. Thanks.