My phone galaxy GT-I9003 is stuck in flight mode and not able to detect Sim card. I want to disable the airplane mode in order to return to normal state. After a long press on power button, I do have the "device options", however nothing happens when I press Airplane mode (airplane mode enable). I am stuck in airplane mode

Have you experience this? Is it a known bug? How can I disable airplane mode.
Go to SETTINGS > WIRELESS AND NETWORKS and uncheck AEROPLANE MODE from there.

If that doesn't work, remove the battery and SIM card, wait 1 minute and re-insert SIM + battery and restart.