> Furthermore, commas are no good because they're already a separator
> for separate addresses in a single field. (Admittedly we already
> allow a syntax like John F. Bloggs <email@host> which is not
> permitted by RFC822.)
Why?
'John F. Bloggs <email@host>' seems to be a valid RFC822 address...
It's not allowed, actually. To be precisely legal, it needs to be
quoted as "John F. Bloggs" <email@host>.