yum db error - what to do?

[Dave Stevens]

trying to do yuom install scribus I get this:

Component: Software Installer
Summary: TB6b5e0e87 config.py:661:_getsysver:TypeError: rpmdb open
failed

Traceback (most recent call last):
  File "/usr/sbin/system-install-packages", line 243, in ?
    main()
  File "/usr/sbin/system-install-packages", line 236, in main
    pkginst = SinglePackageInstaller()
  File "/usr/sbin/system-install-packages", line 57, in __init__
    GraphicalYumBase.__init__(self, False)
  File "/usr/lib/python2.4/site-packages/pirut/__init__.py", line 124,
in 
__init__
    plugin_types=(yum.plugins.TYPE_CORE,))
  File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 125, in 
doConfigSetup
    self.conf = config.readMainConfig(startupconf)
  File "/usr/lib/python2.4/site-packages/yum/config.py", line 598, in 
readMainConfig
    yumvars['releasever'] = _getsysver(startupconf.installroot, 
startupconf.distroverpkg)
  File "/usr/lib/python2.4/site-packages/yum/config.py", line 661, in 
_getsysver
    idx = ts.dbMatch('provides', distroverpkg)
TypeError: rpmdb open failed

Local variables in innermost frame:
installroot: /
ts: <rpmUtils.transaction.TransactionWrapper instance at 0x9323b0c>
distroverpkg: redhat-release

I get very similar messages doing just yum with no arguments.

Ideas?

Dave