python - rc: Fix for 2.4.

Log Message:
-----------
Fix for 2.4.

2.4 appears to unconditionally expand latter parts of (x and y or z).
This is a problem if the index does not exist. ugh.

Modified Files:
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rc/src:
renv.py (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/python/rc/src/renv.py.diff?r1=1.2&r2=1.3)