I don't remember the details, but originally had the same trouble. I think a "/" at the end of a url got me somewhere. 
I have defined...

URL = http://somewhere.edu/elog

...in the config file, and my redirect looks like this:

Redirect /elog http://somewhere.edu/elog/
ProxyPass /elog/ http://somewhere.edu:8080/
ProxyPassReverse /elog/ http://somewhere.edu:8080/