It means that the RPM has been compiled on a Fedora Release with a higher (lower?) version of the RPM package than you currently have - i.e.: one which provides 'rpmlib(FileDigests) <= 4.6.0-1'. Why are you trying to install an F12 version of this package, and what is your current Fedora Release and arch?
P.S. I've seen this message, and there's no way around, even with '--force' and such: your RPM version does not support this feature.
Last edited by Hlingler; 2nd July 2009 at 12:29 AM.