any advice ??
rpm -e samba3x-winbind
Your problem was that you had samba3x-winbind-3.6.6-0.129.el5 installed which required samba3x-common-3.6.6-0.129.el5.
You are now trying to install samba3x-3.6.6-0.136.el5 which installs samba3x-common-3.6.6-0.136.el5 which causes samba3x-common-3.6.6-0.129.el5 to be removed.
samba3x-winbind-3.6.6-0.136.el5 isn't available in the smeupdates repository, so the upgrade can't be completed.
All of this is stated in the error message you showed.
If you remove samba3x-winbind-3.6.6-0.129.el5 from your system you won't encounter this problem.