(disclaimer) Below is a shotgun approach. See later posts for better solutions.
From `man samba_selinux` :
"You can disable SELinux protection for the samba daemon by executing:"
Code:
setsebool -P smbd_disable_trans 1
service smb restart
The above worked for me on FC4 (2.6.12-1.1447), with selinux-policy-targeted-1.25.4-10.1