diff --git a/mail-server/users.nix b/mail-server/users.nix
index e3fad42..c55375c 100644
--- a/mail-server/users.nix
+++ b/mail-server/users.nix
@@ -46,7 +46,7 @@ in
   config = lib.mkIf enable {
     # set the vmail gid to a specific value
     users.groups = {
-      vmail = { gid = vmailUIDStart; };
+      "${vmailGroupName}" = { gid = vmailUIDStart; };
     };
 
     # define all users