best advice?- Using unlocked iphone overseas..

[sneaky squirrel]

Hi, I will be travelling to Singapore and Malaysia in a few weeks, and I was hoping to get advice for using my iphone overseas.

Currently im using an unlocked iphone in australia with an Optus sim.
To get edge to work at home, I use the optus apn settings in network.

If I want to get data while im away, do i need to put in the local carrier apn settings, or will i just continue to use the optus data service?
Does anyone know if charges are higher when you use edge while overseas like call 'roaming' charges?

My plan while OS is to limit my phone calls as they are expensive, use my iphone to sms, and connect to free wi-fi if available, and use edge if i need to..
Is there anything else to look out for, think about when using iphone OS??

many thanks!

[GR81]

make sure edge is turned off when overseas, the roaming charges will kill you!

[Eurisko]

You'll be charged your regular data, plus roaming charges on top, and that's what'll kill your wallet. Resetting your APN to a local carrier won't make a difference. Best advise, when you're overseas, make sure Settings -> General -> Network -> Data Roaming is turned off. Just use local WiFi wherever its provided free.

[sneaky squirrel]

thanks so much to you both!
.. last thing i want is a surprise bill when i get back!