Recovering disk space from deleted file

[matt-urrlRJtNKRMsHrnhXWJB8w at public.gmane.org (Matt Shields)]

I've come across this situation one other time but can't remember how I
fixed it.

There's a Jetty/Java process that had a 19GB log file.  I stopped the
process, mv the jetty.log to jetty.log.old, started the jetty process again.
 Then I deleted the file.  DF and DU still says that the space is still
being take up, but checking the directory the file is gone and checking lsof
I don't see the file being accessed, so it had to have been deleted.

-matt