samba - Feb 2010 - Issues with latest build 3.4.5

Same share that works fine with older version 3.0.27 as "guest" does
not
work with latest 3.4.5. For anyone (guest) while version 3.0.27 maps fine
w/o any password, server with 3.4.5 errors out. Has something changed on
newer releases that checks group membership before mapping, even as a guest?

        force group = agroup
        guest ok = Yes

Thanks.