Android 4.0 issue with Activity Stack and Task Sta

Question

I am developing an app for android 4.0. I am confuse with Task and Activity stack for Android 4.0.

suppose I have activities X,Y,Z of the same app. so when i fire Home intent with flag activity_clear_task i am navigated to home which is expected.

case I when I am in some other app's activity say setting-> manage application and if Home intent is fired from my activity i am able to navigate to home but when i click on menu i don't see any thing thing is the new task is started ?

I cant provide screenshot as m new to stack-overflow and my reputation is <10

case II when i fired home intent while i am in my aap then i am navigated to home and i am able to see the menu.which is expected.

I cant provide screenshot as m new to stackoverflow and my reputation is <10

case III follow the procedure as case I and relaunch the app using to app using long key pressed and again home intent is fired i am navigated back to home and now i can see the menus when clicked on menu

I cant provide screenshot as m new to stackoverflow and my reputation is < 10

my question here is why this is happening it works perfectly well on 3.0 and lower. is it because of new implementation of task and activity stack. i am confused. please see the above screen shots for case I and case II.

also i faced activity stack issue about the activity stack behavior in 4.0 as when i launch setting->manage application come back to home and launch contact app and go to its sub-activities and press home button and navigate back to setting now press back key until u exit setting and u'l see something strange as u are navigated to home not the contact app.

i also saw this post but there are no answers.