trying to add a site in multisite

Hi,

I’m in http://otmamto.com/wpmu/wp-admin/network/site-new.php , trying to add a new site but am being rejected, “Missing or invalid site address”.

it didn’t accept letsnail.com

My multisite sits http://otmamto.com/wpmu/ , is it possible when the multisite is in a folder (eg. wpmu and not root) that it doesn’t ?