EXC_BAD_ACCESS on iPad device

Question

hello i'm a newbee and developp a nice application for iPad. Works well on the simulator but on the device :telling me EXC_BAD_ACCESS i build and debug and it's doing EXC_BAD_ACCESS on the last line...

...

calculrecord = [[UILabel alloc] init];

calculrecord.text = [[NSUserDefaults standardUserDefaults] stringForKey:@"daterecord"];

self.dateDR = [self.dateFormatter dateFromString:calculrecord.text];

i really do not understand because it was working good 2 days ago on the device. i try and try and try again. If I take this line away, my application load well on my iPad (but i don't get what i want without this line..) can someone help me ?? thanks a lot