iCal invites gives Facebook error?

I have been trying to send an iCal invite to someone and keep getting the following message:

"This message was created automatically by Facebook.

The person you’re trying to reach may only accept emails from people they're connected to on Facebook. Please add noreply@icloud.com to your Facebook account and try again.

Reporting-MTA: dns; 10.148.126.39

Arrival-Date: Fri, 23 Nov 2012 20:32:39 -0800"

I have sent this person emails before and not had any issues until recently. I am sending the invite to the same @me.com email this person has always had but it seems to think I'm inviting the person through Facebook. In any case, I am already connected to this person on Facebook so the message makes absolutely no sense. Has anyone come across this issue before?

Thanks,

Liz