Okay, I have heard of this being done, but can't find anything concrete. I have heard of people cutting down to size a regular sim card from an AT&T phone and using it in the iPad. I did that. Fits fine, but something is not working. who knows, maybe it doesn't really work, but the sim card I am using is a 3g card from a spare phone. Maybe I was hoping for too much.
Any thoughts out there anyone? I keep getting the error, "the connection to the server was lost, please try again later"

You can use regular sim card in the iPad just cutting your regular sim card (for the best result you Should use sim card which use for modem 3G or already activated for Internet connection) to ipad (we called it micro sim)

Yes, you'll need a sim card that already has a data plan

I have cut it down. Is there a difference between a 3G sim card, and a 3G data plan card?

I use a twincard from my iPhone 4, the twincard Is an identical copy of my cellphone simcard.

I resized the simcard to the microsim format and therefore Im able to send sms/mms stright from my ipad as well, just likde from my iPhone.

My Carrier to the iPhone & iPad.
Unlimited data/internet "up to 10 Mbit/s" (No up or down restrictions)
Unlimited sms/mms (To all carriers)
Unlimited voicecalls (To my carrier & verry low fee to other carriers)

The third option Is still not an option on the iPad. "yet"

45usd/month

Where did you buy the twincard?

Thanks

Originally Posted by iPad-Sweden

I use a twincard from my iPhone 4, the twincard Is an identical copy of my cellphone simcard.

I resized the simcard to the microsim format and therefore Im able to send sms/mms stright from my ipad as well, just likde from my iPhone.

My Carrier to the iPhone & iPad.
Unlimited data/internet "up to 10 Mbit/s" (No up or down restrictions)
Unlimited sms/mms (To all carriers)
Unlimited voicecalls (To my carrier & verry low fee to other carriers)

The third option Is still not an option on the iPad. "yet"

45usd/month

Did you get the twin from AT&T?

Originally Posted by drbf

Originally Posted by iPad-Sweden

I use a twincard from my iPhone 4, the twincard Is an identical copy of my cellphone simcard.

I resized the simcard to the microsim format and therefore Im able to send sms/mms stright from my ipad as well, just likde from my iPhone.

My Carrier to the iPhone & iPad.
Unlimited data/internet "up to 10 Mbit/s" (No up or down restrictions)
Unlimited sms/mms (To all carriers)
Unlimited voicecalls (To my carrier & verry low fee to other carriers)

The third option Is still not an option on the iPad. "yet"

45usd/month

Did you get the twin from AT&T?

Swedish carrier.

If anyone in bangalore wants to convert your normal sim to microsim for iphone 4 or ipad within 5 minutes then You can call me at 9916404237 ... sim conversion Rs.50

I hacked my SIM following instructions online, It caught signal immediately.
I didn't bother testing it because data transfer is expensive in Mexico. I will soon.

The hack is delicate, you need a steady hand and a sharp knife and/or scissors.
Before you try your card, make sure it includes data, because voice plans won't work.

Different carriers will make you jump through hoops to get connected, I find Mexico certainly simple to connect, therefore is expensive, they just want your money.

My iPad may have come unlocked because I bought it in Mexico, don't know whether US iPads come locked but that would be silly, since they're not affiliated to Apple I don' think.

Doing a hack on an Apple product needs a little research, you may need the warranty.