diff --git a/Mac/Lib/EasyDialogs.py b/Mac/Lib/EasyDialogs.py
index b42674a3fc5..742daa42329 100644
--- a/Mac/Lib/EasyDialogs.py
+++ b/Mac/Lib/EasyDialogs.py
@@ -213,7 +213,7 @@ def test():
 			"So far, so good!", "Keep on truckin'" )
 	bar = ProgressBar("Progress, progress...", 100)
 	try:
-		appsw = MacOS.EnableAppswitch(0)
+		appsw = MacOS.SchedParams(1, 0)
 		for i in range(100):
 			bar.set(i)
 			time.sleep(0.1)
@@ -223,7 +223,7 @@ def test():
 		time.sleep(0.3) 	# give'em a chance to see the done.
 	finally:
 		del bar
-		MacOS.EnableAppswitch(appsw)
+		apply(MacOS.SchedParams, appsw)
 
 
 	
diff --git a/Mac/Lib/FrameWork.py b/Mac/Lib/FrameWork.py
index da07d139224..caaf81cc37d 100644
--- a/Mac/Lib/FrameWork.py
+++ b/Mac/Lib/FrameWork.py
@@ -143,7 +143,7 @@ class Application:
 	
 	def mainloop(self, mask = everyEvent, wait = 0):
 		self.quitting = 0
-		saveyield = MacOS.EnableAppswitch(self.yield)
+		saveparams = apply(MacOS.SchedParams, self.schedparams)
 		try:
 			while not self.quitting:
 				try:
@@ -154,9 +154,9 @@ class Application:
 					# applications.
 					break
 		finally:
-			MacOS.EnableAppswitch(saveyield)
+			apply(MacOS.SchedParams, self.schedparams)
 	
-	yield = -1
+	schedparams = MacOS.SchedParams()
 	
 	def do1event(self, mask = everyEvent, wait = 0):
 		ok, event = self.getevent(mask, wait)