About SMS message period of validity. A brand new Iphone 3GS phone has the SMS message validity period defined by operator, usually 3 days. If a message cannot be delivered in this defined time to the destination, (for example the receptionist keeps phone switched off) message will be destroyed? It seems to be not possible to change this setting in Iphone 3GS, not just as usually in most cell phones, from 1 hour to 7 days or even more!!? Also one can't get no info if or when a message has been delivered, or is it still waiting for delivery or has VP exceeded..! It can be get also by typing before message one of marks *K#, *N#, -K-, (etc., depending on operator). If and when JailBreak has been done, e.g. using program "Blackra1n" the validity time is 10h. However, there in program "biteSMS" is 'Message delivered' facility included, but I haven't found any program which has this mentioned facility for changing the period of message's validity. This has been often needed to ensure that an important message really has been delivered and that it has not been erased before recipient has seen it! For me 3 days is mostly long enough, but that 10 hours is far too short and about this limit would be necessary for many JB users to know e.g. via public areas. Can anyone tell, does JB or any after installed program really change that period? All comments about this matter will be welcome!