that was a long time ago
search the thread for the pages while me and ammyt where trying to solve it

and how :
when you get call
the screen will be on
then the cpu_normal will be activated
(even if you are talking the vfs will stay at 100)

then if you end the call
you will lock your phone or leave it to autolock or just not do anything
in all these cases : cpu_sleep will be activated