[CentOS] Python resource module returns just zeros

I'm using a call to the resource module's getrusage method.  On openSUSE
this works, on CentOS [python26-2.6.5-3.el5] it 'works' but just returns
zeros for the memory utilization values.

resource.getrusage(resource.RUSAGE_SELF).ru_maxrss

openSUSE: returns 5512
CentOS:   returns 0

Anyone know what condition causes this?  Or is there a better /
more-reliable way to check memory utilization of the current process [from python]?
-- 
Adam Tauno Williams <awilliam at whitemice.org> LPIC-1, Novell CLA
<http://www.whitemiceconsulting.com>
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