what about optus? I dont know what APN settings are being used on my new phone. Is there a way of finding out?

Look on the first page.

If you can see Cellular Network Data, then you can edit the APN.

If you can't, then you can't.

See chrome's post here, if you want the visual way:
http://forums.mactalk.com.au/570993-post20.html

bugger, so if I cant see it (basically if i'm not on telstra) there is no way to change the APN settings after swapping a sim.

seems kinda dim

maybe once the phones unlocked they will put that feature back into the unlocked firmware?!?!

Yes this sucks which is why I made the thread. It was possible on the 1st gen without any troubles.

And according to Apple's documentation, you are able to change APN once the phone is unlocked. So yes, it is possible once unlocked.

Also, it is at the discretion of carriers whether to allow users to change APN etc under their locked phones. Apparently Telstra allows this, so good on them for that.

I was considering getting an iphone outright and continuing on my current contract
($49 maxicap) However this uses data at a rate of $1 per 5 minutes and I'd really like control over whether that was turned on or off obviously. I tried talking to vodafone people and just got the impression even their staff have no idea how data is being counted at vodafone so it's not that desirable after all.

My alternative was to switch to optus in september when my vodafone contract runs out.
Not sure exactly how that would work but I'd defiantly want to keep my number, does anyone
know whether Optus lets you see your APN settings ? if not I guess the unlocking of the phone
might serve more useful as an APN unlocking feature. sucks to have to pay $85 bucks just to get control over your data usage though...

perhaps an app in the app store which disables/enables data at different levels is what we need ?

does anyone think it is worth it for me(vodafone locked outright/prepaid) to unlock it so i can control my data usage

$75 from Vodafone.
If you are thinking of unlocking in future, you might as well pay now and get it unlocked and you can fiddle with the Cellular Network Data settings (APN, username, password).

Unlocking also increases resale value. I will be doing this, but after spending ~$800 on the iPhone two days ago, I don't want to spend another $75 just yet! I'm broke...

apple should have just had a "Disable cellular data" button

i just went to vodafone the guy was clueless on how to do it so he inputed it online for me for free i will get the unlock code in 3 days

Let us know how it goes.

If the guy was clueless then I think he has no idea what he's doing...

The online system does not work for iPhone yet. Try it yourself:
Handset Unlocking - Identify Handset

There is no "code" that you enter to unlock. It is via iTunes.

he rang up the customer care and they said he had to do it from there ill see

my old sim was also stuffing up so he gave me a new 3G sim for free

I have had my iPhone unlocked with Optus and have no option to change the APN setting on it. I've tested this with a Telstra sim card and the option doesn't show up either. The only thing I haven't tried is to restore it with the Telstra sim card installed. This pretty much limits me to only making phone calls with a Telstra SIM card installed.

Grrr this is what I was afraid of.

Some many differing reports on these forums.

Some say the sim controls whether the APN information can be seen/edited, some say its the locked or unlocked status of the phone.

I have an Optus 3G sim installed in my iPhone 3G, i'm on post paid 12 month contract and had Optus unlock my iPhone yesterday (which required me to do a firmware restore getting v2.0 (5A347) in the process.

To date I have no other sim to install and test, so can't comment on whether the unlocking was successful, or whether the APN settings reappear with another sim installed from the likes of Telstra or Vodafone.

APN information can be pushed out onto the iPhone (configured on the iPhone side), so that removes one of the obstacles.

According to this page:
iPhone: How to view or edit the APN setting

It says once unlocked, you should see APN settings. Or if your carrier allows you to.

As for verifying an unlock, there's just one way to do it and you need to grab hold of another carrier's SIM.

Ta Huy