yum updates corrupting rpmdb

[Joe Smith]

This is the second update in as many days that has resulted in a 
corrupted rpm database for me. I was able to fix yesterday's with a 
--rebuilddb and 'yum clean all' but before I go through that little 
exercise again, is anyone else seeing problems? Any suggestions how to 
debug this?

# yum update
( lists a dozen or so packages to update, including firefox...
   ...I say 'y'...
   ...10 minutes later the terminal history is filled with:
rpmdb: PANIC: fatal region error detected; run recovery
rpmdb: PANIC: fatal region error detected; run recovery

and yum won't die except by 'kill -9'

# rpm -qa
rpmdb: PANIC: fatal region error detected; run recovery
error: db4 error(-30977) from dbenv->open: DB_RUNRECOVERY: Fatal error, 
run database recovery
error: cannot open Packages index using db3 -  (-30977)
error: cannot open Packages database in /var/lib/rpm

Not out of space...
# df /var/lib/rpm
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/sdb7               497829    205804    266323  44% /var

and there are no kernel disk error messages.

Is there some "run recovery" that's different than --rebuilddb?

<Joe