He started it

Place blame where blame is due.

Cardspace, SAML, and OpenID go into a bar.

The bartender says to Cardspace 'I'm gonna have to see some ID before I serve you'. Cardspace shows its ID and then orders a beer.

Bartender says the same thing to SAML, which also orders a beer.

When the bartender sees OpenID, he says 'Im sorry but you are going to have to leave'.

'But why' says OpenID 'Im of legal drinking age and I have ID to prove it.'

'Im sure you do' says the bartender, 'but I don't know how to ask you for it'.