PostgreSQL Upgrade Difficulties

I have just tried upgrading to 7.02 using the rpm. I am
using RedHat 6.2, Kernel 2.2.14-5.0. After various
difficulties and an unsuccessful scour through the mailing
list archives, I uninstalled everything and reinstalled.
Things appear to go well, and running the postgresql start
script chugs away, gets and ends up with:

Checking postgresql installation: looks good!
Starting postgresql service: failed.

I'm not really sure how to proceed. Any suggestions would
be welcome.

Sean.