How could I locate the crash code from the crash log in my ip4 device? As the crashed thread 0 presents a serial frameworks and main.m, I couldn't locate the accurate code launched this crash and debug it. Any suggestion? Thanks in advance!

Incident Identifier: B6BD84B7-CE0A-485D-A877-0FD0F5B75933
CrashReporter Key:   b0b97a37f2a1e4911ce2ef34e1793e028463bb67
Hardware Model:      iPhone3,1
Process:         myApp [11615]
Path:            /var/mobile/Applications/28AE71F2-36CA-4A87-83D9-07DF2DFE74F1/myApp.app/myApp
Identifier:      myApp
Version:         ??? (???)
Code Type:       ARM (Native)
Parent Process:  launchd [1]

Date/Time:       2012-06-09 21:12:22.792 +0800
OS Version:      iPhone OS 5.1 (9B176)
Report Version:  104

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x0000000b
Crashed Thread:  0

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libobjc.A.dylib                 0x36721f78 0x3671e000 + 16248
1   MapKit                          0x34e7ace6 0x34e68000 + 77030
2   CoreFoundation                  0x3525f1f4 0x35247000 + 98804
3   Foundation                      0x311b6740 0x31112000 + 673600
4   CoreFoundation                  0x352d4acc 0x35247000 + 580300
5   CoreFoundation                  0x352d4298 0x35247000 + 578200
6   CoreFoundation                  0x352d303e 0x35247000 + 573502
7   CoreFoundation                  0x3525649e 0x35247000 + 62622
8   CoreFoundation                  0x35256366 0x35247000 + 62310
9   GraphicsServices                0x36552432 0x3654e000 + 17458
10  UIKit                           0x3234ce76 0x3231b000 + 204406
11  myApp                           0x0001bac0 main (main.m:16)
12  myApp                           0x0001ba80 start + 32