Hello Folks,
FWI (and slightly OT), we have had no end of troubles with the standard 3.0.10-EL4 Samba RPMs, specially regarding MS SMS installations. We have fixed all of them just by upgrading to Samba 3.0.23d, rebuilt (with a simple "rpmbuild --rebuild") from the SRPM available at http://ftp.sernet.de/pub/samba/src/samba3-3.0.23d-30.src.rpm
We have not yet tried the new 3.0.24 version, but we assume it would work just as well.
If you use LDAP authentication, there's a change in the Samba schema regarding indexing, mostly harmless but you will have to rebuild the LDAP indexes using slapindex (it's on the Release Notes).
If the upstream vendor used more up-to-date versions of some packages (3.0.10 is more than 2 years obsolete, for example) I think there would be much less crying and gnashing of teeth, but them maybe it would be much less fun too :-)
Best Regards,