The example configuration in the aforementioned URL uses add group script = /usr/sbin/groupadd %g. This is flawed. When someone tries to add a group called for example "Meany Family", then groupadd "Meany Family" will be called with this result: root@oberon:~# groupadd "Meany Family" groupadd: Meany Family is a not a valid group name
Samba passes the task to create a group through to the utility that is specified as the "group add script". The Linux groupadd command is an operating system tool. For some reason the more recent version of this does not permit the use of upper-case characters or the use of spaces in the name. Do you have a better suggestion? This is not a Samba issue, it is an operating system utility issue. I will try to document this fact. We are limited by what the OS vendor implements. Sorry. - JHT
John is handling this bug.
updating qa contact
Well, now that I have looked further into this bug report it appears that in section 11.4.1 of the current HOWTO this very issue has been documented. Case closed. - John T.