thanks for your answers,
the original firmware was 40p.i flash to 41p stock.is this fw in the warranty?
but ,problem is still keeping on.
but i discovered that,this problem is appearing only when the battery is weak.
but there is no batt.warning. batt indicator is full.
when i carge the phone fully, there is no problem for at least one day.
after that i frequently find the phone locked.but batt.indicator is full.
it starts normaly by remove-install the batt many times without no batt warnnings. :'(
the phone is new.
in my country,warranty procedures long take long time (e few mounts).and generally
they claim "liquid contact",no warranty