How can I send a Privatemsg using Rules and have the name of the site as the sender? I am using the Privatemsg and Rules module and I am trying to set up an automatically generated welcome message to new members registering on the site. This message will go into the new member's inbox.

I do not see a token that would allow the site's name to be the sender. All I see is the token for the logged in user. As expected, this doesn't trigger the message. 

I have toyed with the [account] token. So when John creates an account, the message comes from John himself. This would be acceptable but it isn't consistent: Sometimes it works, sometimes it doesn't.

I know some tokens exist that are not always displayed. Does anyone have the name of the mysterious token? Or the magic to get this to work?
You could create an account for sending the messages and in rules, use direct input and enter its user id. That way, you could also see replies to welcome message.