Tried to update last night because there a few upstream security patches you really want to have installed on your system, especially when you run a website or remote webapps on your server. Unfortunately the downgrade trick did not work this time. The upgrade will force samba libsmbclient packages to version 3.6.23-30, a downgrade will install 3.6.23-25, which gives you the same problem. The last working version is 3.6.23-23.
The fix is to donwgrade twice (may be more in a few weeks time) untill you see version 3.6.23-23 gets installed.
Or use the yum update command and exclude the libclient packages from the update.
Can anyone explain why this is topic is marked solved? I think it should not be, the real problem still exists, hopefully an upstream fix will deal with that. This is just a temporary workaround which is about to fail again somehow any time soon.