"It seems you've hit some kind of bug causing SMB shares not to be visible. As many other commenters have pointed out, this *does* work by default"

No, it doesn't. If he was unable to see his Samba shares without any form of tinkering on his part whatever, then SMB support is broken in Mandriva. MANY other distro's do not have this issue at all, so why then does Mandriva?