[Samba] share premissions help

[Lozej Radovan]

hello

i would like to set premission for share like this:
user can:
-create new file
-read file
user cant:
-delete file
-modify file

is it posible? i really dont know how to do it, but i relly need it.

..and another thing
if i set create mask = 0740 and force user = root
why can another user still delete this file, although root is the owner 
with 740 mask

can someone help?

bye bye
rado.