execf not working

Hi people,

I'm running ratpoison on Ubuntu, using the version found in the
repositories.

I've got my screen split into two frames, 0 and 1. Say I have an xterm
in frame 0. In that xterm, I type

ratpoison -c "execf 1 xterm"

Things run as planned: A new xterm is opened in frame 1. However, if I
try with a heavier-duty program, say, chromium...

ratpoison -c "execf 1 chromium-browser"

... chromium opens in the current frame, frame 0.

I've tried this in Ubuntu Lucid (ratpoison v1.4.2) and Oneiric
(ratpoison v1.4.5) and find the same behavior in both.

Am I doing something wrong?

Cheers,

Kelly