Right click in pan/zoom not working for macosx backend

Hi,

When using the macosx backend and the pan/zoom tool, I cannot zoom
in/out with the right mouse button. The left mouse button does the
panning as usual. This only seems to happen with the macosx backend.
Other backends (GTKAgg, WXAgg) work fine. I am using ipython [-pylab]
and matplotlib from svn, revision 6979.

Is this bug know? I couldn't find a reference to it.

Cheers,

Tiago