This syntax worked for me:
I'm running xine version 0.99.6 under UBUNTU 9.10 on an AMD64 processor.
I ran across this syntax specification at the home page for the Totem player (I would post the URL, but the forum won't let me since this is my first post). I tried the same syntax for xine and it worked.
The double-colon delimiter ludist recommended worked for me too. The space-delimited version that 1veedo used did not work for me, but I'm using xine, and don't have gxine installed.