On Monday, Jun 30, 2003, at 11:00 US/Eastern, Henning Makholm wrote:
I dimly remember that there may be jurisdictions (America?) where
any of several joint authors can authorize copying if only he
splits the profits fairly with other authors.
Yep. In the US, it's called a "joint work" and each of the authors separately have a right to grant non-exclusive licenses, without the consent of the other authors, though profits must be shared.