David Grigg1 & Tobyiii:
I looked at the screen shots of David's phone and I noticed something. It appears that David is in Australia and on the Telstra network. Imust first say that I don't know anything about this cellular carrier and it's infrastructure so what I'm about to say may not make sense. But before I do, Ihave some questions.
(1) Are you on a data plan with the carrier?
(2) Have you always had this issue or is it new?
(3) Is it an intermittent issue or it has never worked?
(4) Is this a jailbreak iPhone or was it purchased from thecarrier?
(5) Have you had any other technical issues with the iPhone -hardware or software related?
(6) Are your friends on the same network having similar issues?
Here goes my analysis. One reason you can't see calendar optionson the phone is because of hardware or software, or both conflicting with the carrier's cellular signals. What I mean by this is that for some reason yourphone thinks that it does not have a data push/pull function enabled on yourdevice. This function is turned on by the carrier to your iPhone via a signal to the device.
How did I come to this conclusion? I did some basic tests withan iPhone 4 and iPhone 3G and iPhone 3GS. I found that when I simulated adisconnection from the carrier's signal I noticed the Calendar optiondisappeared as a feature to adjust on all three phones. In another word, theoption was totally gone from the screen.
There are only three ways this can happen:
(a) A hardware defect causing intermittent receiving of data push/pull signal
(b) A software malfunction is causing the absence of hardware/software receipt of the data push/pull signal
(c) The SIM chip has a defect.
I would recommend going back to the carrier and showingthem your phone. Compare the screen of the display unit next with yours. If the display unit has the calendar function then your phone should as well. I would recommend them replace the SIM chip first. If that doesn’t take care of it, then it is an internal hardware/software conflict and can only be addressed by a technician. You willhave to send it in for repairs or replace it with a new one.
Let me know if this helps...