is it possible to map several unix group to "domain users"
i try like that : 
net groupmap add ntgroup="Domain Users" unixgroup=G1 rid=513 type=d
it works
then i try for a second group, it fail
net groupmap add ntgroup="Domain Users" unixgroup=G2 rid=513 type=d
but when i try to do that with a ldif file : 

dn: cn=g1,ou=Groups,dc=ldap,dc=fr
objectClass: posixGroup
objectClass: sambaGroupMapping
cn: g1
gidNumber: 2000
sambaSID: S-1-5-21-3556451643-3619796698-2968123708-513
sambaGroupType: 2
displayname: g1

dn: cn=g2,ou=Groups,dc=ldap,dc=fr
objectClass: posixGroup
objectClass: sambaGroupMapping
cn: g2
gidNumber: 2001
sambaSID: S-1-5-21-3556451643-3619796698-2968123708-513
sambaGroupType: 2
displayname: g2

there is no error message, is it correct or samba doesnt like group mapping several unix group to one nt group ??
then is there a way to do that ?