+@item
+@findex defclass
+@findex ensure-class
+@findex ensure-class-using-class
+@findex sb-mop:ensure-class
+@findex sb-mop:ensure-class-using-class
+@findex find-class
+@findex class-name
+the class named by the @code{name} argument to @code{ensure-class}, if
+any, is only redefined if it is the proper name of that class;
+otherwise, a new class is created.
+
+This is consistent with the description of @code{ensure-class} in AMOP
+as the functional version of @code{defclass}, which has this behaviour;
+however, it is not consistent with the weaker requirement in AMOP, which
+states that any class found by @code{find-class}, no matter what its
+@code{class-name}, is redefined.
+