Index: pym/portage/sets/libs.py
===================================================================
--- pym/portage/sets/libs.py	(revision 11831)
+++ pym/portage/sets/libs.py	(revision 11832)
@@ -27,7 +27,8 @@
 		reg = self.dbapi.plib_registry
 		consumers = set()
 		if reg:
-			for libs in reg.getPreservedLibs().values():
+			plib_dict = reg.getPreservedLibs()
+			for libs in plib_dict.itervalues():
 				for lib in libs:
 					if self.debug:
 						print lib
@@ -35,6 +36,10 @@
 							print "    ", x
 						print "-"*40
 					consumers.update(self.dbapi.linkmap.findConsumers(lib))
+			# Don't rebuild packages just because they contain preserved
+			# libs that happen to be consumers of other preserved libs.
+			for libs in plib_dict.itervalues():
+				consumers.difference_update(libs)
 		else:
 			return
 		if not consumers: