Can system classes be generalized instances of more than one standard metaclass?

From: Paul Dietz
Subject: Can system classes be generalized instances of more than one standard  metaclass?
Date: Mon, 03 Feb 2003 21:55:45 +0000
Message-ID: <3E3EE560.29DAB69F@motorola.com>

Is it compliant with the standard for system classes
to be generalized instances of more than one metaclass?
For example, could one be both a built-in-class and
a standard-class?

	Paul