RPM Database broken

[Francois Massonneau]

Hello,

I got a pb yesterday, when I wanted to run the usual "yum update" command.

I got the following message :

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
Traceback (most recent call last):
  File "/usr/bin/yum", line 27, in ?
    yummain.main(sys.argv[1:])
  File "/usr/share/yum-cli/yummain.py", line 75, in main
    base.getOptionsConfig(args)
  File "/usr/share/yum-cli/cli.py", line 170, in getOptionsConfig
    self.doConfigSetup(fn=opts.conffile, root=root)
  File "__init__.py", line 82, in doConfigSetup
  File "config.py", line 271, in __init__
  File "config.py", line 383, in _getsysver
TypeError: rpmdb open failed

Then I tried to delete the /var/lib/rpm/__db.* files, and reran the command :
rpm -vv --rebuilddb

Same result :-( :
rpmdb: PANIC: fatal region error detected; run recovery
erreur: erreur db4(-30977) de dbenv->open: DB_RUNRECOVERY: Fatal error, run 
database recovery
erreur: ne peut ouvrir l'index Packages en utilisant db3 -  (-30977)

I deleted again the __db.* files and reran the same command.
This time, no more error messages.
It seemed it was ok, but nope ;-(

I can't any longer update a package, nor see the packages I installed a while 
ago.
It seems that just a few packages are in the newly created (or repaired) 
database, but not all packages installed by me, since I put that FC4 on my 
system.

Is there a way to rebuild the database with all the packages installed on that 
computer, if so, how, and get a system that I can update as I want.

Thank you so much for you help, because I'm totally lost. Francois