I've got an 8gb iPhone on O2 in the UK and I'm on 1.1.4 (Roll on June!)

Every now and again my iphone stops receiving texts and I have to send another one to get it to start again when I have a flood of new messages all come through at once....My friends are starting to think that I'm ignoring them!

I was on O2 on my old phone a Sony Ericsson and this never happened so I'm wondering if this is a known problem that others have experienced or is it just my phone that's a bit screwey?
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I've never had that problem (that I'm aware of). Can you make and receive calls when the messages aren't coming through?

Ed.
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Yup. Everything else works fine. Calls, Internet, wi-fi etc. But I'll be in the middle of a conversation with someone then nothing. When I finally send them a text I get all the messages they've sent in that time thinking I was ignoring them.

It's very odd. Can't even think when it first started doing it either. Always I think.
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Weird. I'm not even sure whether that would be a phone or O2 problem.

Have you tried the usual restart, reset, restore on your iPhone?

Ed.
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Yup. I've had to do 2 restores on my phone and nothing's changed. I've even tried turning it off and on again :)

I figure if no-one else is having this problem then it's not with O2 or more people would experience it surely?
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SMS has never been an instantaneous delivery service at the best of times, and I wouldn't be surprised if it's a carrier problem.... I've had similar problems on various devices I've used over the years. It's generally rare, but when it does happen, it tends to delay all SMS messages for a couple of hours.

It's also important to note that the nature of SMS delivery is such that the phone does not "poll" for SMS messages (this is true of any cell phone, not just the iPhone). So if you're out of coverage, or the network is overly busy and can't find your device when it's time to deliver the SMS message, then there could be a delay of up to an hour before the network tries to retransmit it to your phone. I frequently have this problem when I'm in the subway (out of coverage) -- SMS messages sent to me while I'm underground sometimes don't show up until almost an hour after I surface.

Unfortunately, it's difficult to say for certain whether your problem is the network or the phone, and the only way to actually test this would be to get your hands on another phone and put your SIM card into it and see if it has the same SMS problems. If so, then it's definitely a network issue.
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My phone's not unlocked. I know that will cause a problem if I try to put another sim into it but will it cause any problems if i put my sim into another handset?

EDIT: I mean for example my old Sony Ericsson which I still keep to listen to the radio on which was also on O2. Will my iPhone sim work in that?
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Your iPhone SIM card should work in any other phone that's unlocked or even a phone that's locked to the same provider. The only way you'll have a problem is if the other phone is locked to another cell phone carrier.

The SIM-lock is based on the phone, not the card, so that itself won't be a problem. There are some variations between SIM cards, but they're generally backward-compatible without any problems (ie, newer SIM cards can be used in older phones, but not necessarily vice-versa).
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