rkhunter reports change in file properties, but I don't see that they've been updated by yum

I just used the command "yum provides /path/binary" on a 64bit CentOS box I have here and all of those binaries are part of the util-linux package. Which is listed in your recent updates.

Is it possible that you have used ''prelink'' at some point between now and 3rd September 2009. Prelink has a MD5 flag:

--md5 

This is similar to --verify option, except instead of outputing the content of the binary or library before prelinking to standard output MD5 digest is printed. See md5sum(1).

Check those binaries with that, it should then match your recorded value if it's prelink causing them to change.