There's an issue with COnlficts: that affects all versions of rpm back to 3.0.2
that was discovered by Mancoosi SAT solvers ~15 months ago:
Conflicts: with missing values aren't compared correctly.
The failure symptom(s) in CentOS 5.5 (and in RHEL) are (at least) these:
error: Failed dependencies:
glibc > 2.5 conflicts with glibc-common-2.5-49.i386
samba-common < 0:3.1 conflicts with tdb-tools-1.1.2-51.el5.i386
Because its glibc and samba, I'm taking the trouble to report the issue here.
The issue is being tracked at
https://bugs.launchpad.net/rpm/+bug/633208
hth
73 de Jeff