samba - Mar 2006 - Assigning Permissions on Domain Member Server

Dear all

I have a samba PDC (3.0.21c) with openldap (2.3.19) with 2 domain Member
Servers(samba 3.0.21c) with ACL support
i use domain member servers as  file servers . all my clients are windows
2000 professional.
i have the following scenario at my
I have created 3 groups, "prj1team", "prj1mgr",
"prj1engg".
i have created folder called "myproject" in a samba share called
projects.
myproject has a subdirectory called "alldepts".


now,  no one can create files/folder in myproject directory  but they can
create a files and folder in alldepts folder.
but i don't want anybody to delete the folder alldepts.

myproject(rx)prj1mgr,prj1engg
     | ----alldepts (rwx)prj1mgr,prj1engg
           | ---- files/folders

i have set like this

setfacl -m g:prj1team:rx myproject
setfacl -m g:prj1mgr:rx myproject
setfacl -m g:prj1engg:rx myrproject
setfacl -m g:prj1mgr:rwx myproject/alldepts
setfacl -m g:prj1engg:rwx myrproject/alldeps

in the above permissions, people in group "prj1mgr"and
"prj1engg" are able
to creat files/folders in alldepts.
and when they are in "myproject" directory and  try to delete folder
"alldepts", it gives error access denied .
so far so good, this is what i want.
but when the user of group "prj1mgr" and "prj1engg"
delete folder "alldepts", it says access denied  but it deletes all
the
files and folder inside the "alldepts" directory .
ie it denies the user to delete "alldepts" directory but it does not
deny
the user to delete
all the files and folders inside the alldepts..


Actually what i need is the folder "alldepts"  is used by both groups
"prj1mgr" and "prj1engg" to create files and folder
and both these groups can delete each other files. but i want them to delete
file after changing to that directory (alldepts) , not from outside.

since i have mentioned
setfacl -m g:prj1mgr:rx myproject
setfacl -m g:prj1engg:rx myrproject
it does not allow to delete folder alldepts, but it deletes all files in
alldepts, that i don't want to happen.

Please guide me,