Unusual Gmail spam.

  calendar gmail google invitation spam unauthorized_insertion unusual

Has anyone recieved spam in their Google Mail accounts from 'William Griffin' that comes in the form of an invitation to an event (in the Google Calendar sense)? If so, have you found that it's inserted itself into your Google Calendar (if you have one) even though you haven't accepted or declined it, but deleted it instead?

I received such spam earlier today, read through it, and rather than click "yes/no/maybe" deleted the invitation. Just a few minutes ago, I discovered that it had inserted itself into my public Google Calendar because it sent a text message to my celllphone.

Most unusual.

I'm half-afraid that this is part of a Firefox exploitation attempt, or an attempt at manipulating Google's AJAX implementation. This is probably because I've been reading a lot of whitepapers lately about Gmail account hijacking; I have no evidence at all, so this is all purely speculation. Still, I'm curious about how widespread this is.