cwm on linux/darwin

I hope you'll forgive a naive question. My computer experience is neither 
wide nor deep, but I had little trouble running cwm on a linux box -- 
hooray! However, I get some inexplicable behavior running the same thing 
on on the same files on my mac (OS X, 10.2.8). Here cwm has no difficulty 
with things like cwm --n3 foo.n3 --rdf, but when I try cwm --rdf bar.rdf, 
I get the following errors:

jjc% cwm --rdf content.rdf
Traceback (most recent call last):
   File "/Users/jjc/Desktop/cwm-1.0.0/cwm.py", line 650, in ?
     doCommand()
   File "/Users/jjc/Desktop/cwm-1.0.0/cwm.py", line 426, in doCommand
     referer="")
   File "/Users/jjc/Desktop/cwm-1.0.0/swap/webAccess.py", line 151, in load
     p = rdfxml.rdfxmlparser(store, F,  thisDoc=asIfFrom, flags=flags, 
parser=parser)
   File "/Users/jjc/Desktop/cwm-1.0.0/swap/rdfxml.py", line 16, in 
rdfxmlparser
     import sax2rdf
   File "/Users/jjc/Desktop/cwm-1.0.0/swap/sax2rdf.py", line 99, in ?
     nodeElementExceptions[RDF_NS_URI + a] = True
NameError: name 'True' is not defined

Can someone offer a clue as to what I'm missing?

Jon
__________
J.J. Crump
Dept. of History 353560
University of Washington
Seattle, WA. 98195