In my iPhoto shell, I made a "reload" command that re-exec-ed the script. I could make changes and simply reload right from the shell prompt. I kinda liked the feature, although it doesn't add much value over re-running the command.
However, once I use some AppleScript (or, I guess, AppleEvents) through Mac::Glue, it breaks. I cannot exec anymore. I can run things in subshells though. Whatever causes this happens after the first interaction. Simply loading a glue does not do anything.
I had a really short example of this, but I somehow messed up the simple operation of putting it on my key drive.