How to mass invite members to a social group?

[kh99]

I think I'd make a custom script by copying the code from group.php that starts with if ($_POST['do'] == 'sendinvite'), and changing it as needed.

BTW, I saw your thread about getting a comma separated list of user ids. If this is the only reason you needed that, you could easliy make the script read a space-separated list and solve that problem at the same time.