There is a critical update for samba for centos-5.8 ... we are working on CentOS-5.8 right now and I fully expect it to be released in a week or less. For those of you who can not wait for a week, here is the samba critical update:
http://people.centos.org/hughesjr/c58-samba/x8664/critical/
http://people.centos.org/hughesjr/c58-samba/i386/critical/
These may or may not work without the rest of 5.8 ... for those who do try them, please provide feedback here in this thread.
Thanks, Johnny Hughes