My application is installed from iTunes (by *.ipa)

[beckToan]

Hi all,
I developed a application and create a Cydia repository,
when my application is installed from Cydia, my application run well. But if it is installed from iTunes (by *.ipa),
my application can't open /dev/tty.iap: fileDescriptor = open("/dev/tty.iap", O_RDWR | O_NOCTTY | O_NONBLOCK);
And I can't acess to the iPhone's serial/USB connection to read/write to a device.
Pls give me some advices.

[Broomhead]

Please only start one thread per question!

[beckToan]

I can't open the serial port from inside Apple's sandbox;because of a rule in sandboxTemple.sb, or somewhere else???give me some advices???