Error trying to enable email in development server

I get an error trying to enable email in my server launched from my RTC development environment (Jetty/Derby). This is the message I get on 'Save' from the E-mail Settings admin page:

"An error occurred while saving the configuration properties. Please check your server log for more details"

I don't see a 'log' file anywhere in my server directory structure. The console for the launched server in my RTC development environment does not show any message.

My server directory does not have any spaces in the directory name.

Any ideas?

Thanks,

Dave