I used to symbolicate the crash report in Xcode 5.1.1 directly as there was \"Symbolicate & Re-symbolicate\" in Devices section of Organiser. But after upgrading to Xcod
A plugin is available for Xcode under the Product menu. This plugin is available through Alcatraz package manager or can be directly downloaded from github.
This plugin internally incorporates a shell script that does the set up of running the following commands for manual crash symbolication.
alias symbolicatecrash='/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks/DTDeviceKit.framework/Versions/A/Resources/symbolicatecrash'
find /Applications/Xcode.app -name symbolicatecrash -type f
export DEVELOPER_DIR='/Applications/Xcode.app/Contents/Developer'
symbolicatecrash /path/to/MyApp_2012-10-01_Device.crash /path/to/MyApp.app.dSYM.