Very Computer

I'm getting a series of errors out of rpm (on RedHat 7.1) when I
uninstall packages.

error: cannot open Dirnames index using db3 - No such file or directory
(2)
error: cannot open Requireversion index using db3 - No such file or
directory (2)
error: cannot open Provideversion index using db3 - No such file or
directory (2)
error: cannot open Installtid index using db3 - No such file or
directory (2)
error: cannot open Sigmd5 index using db3 - No such file or directory
(2)
error: cannot open Filemd5s index using db3 - No such file or directory
(2)

Despite these, the database seems to be working, in as much as the
package has been removed...

package fetchmailconf is not installed

... and dependencies are still being recognised when I try to uninstall
other packages.  I have previously removed packages through rpm without
these errors, but there have been several up2date updates since then
(possibly including rpm itself). I haven't seen any errors when updating
packages through up2date.

I've found a couple of other references to these messages on the net,
but only as questions, no answers!

Is this something I should worry about?  Would 'rpm -rebuild' do any
harm?  Any other suggestions?

Any help is appreciated.

Simon.