iLounge reports of a series of data activation issues experienced by original iPad owners when trying to upgrade the AT&T service for the iPad 2. As noted by the iLounge staff, an iPad 2 registered with a an existing, fully paid AT&T data service failed to activate; the second iPad 2 unit, set up with a new account, activated “almost immediately”. AT&T is offering two data plans for the iPad with the first one starting at 250 MB (at $14.99 per month) and a second tier with 2 GB traffic at $25 per month.

iLounge details the two issues original iPad owners may run into:

First, the iPad 2 will not activate. Second, the user will either have to manually swap the Micro-SIM cards between the iPad and iPad 2 units, or AT&T will disable the iPad’s Micro-SIM in order to allow the iPad 2’s Micro-SIM to work. The AT&T representative claimed that a user who chooses the latter option will have to buy a replacement card should they want to restore 3G service to the older model, as the first Micro-SIM will no longer be usable.

To enable the service on multiple iPads, AT&T customers will need to set up different accounts as the carrier’s system isn’t able to register two devices at once. While Apple didn’t make any specific mention of iPad 2 WiFi + 3G upgrade plans for iPad 1 owners, many expected the procedure to be simple and easy as swapping the SIM cards at any time with the same account on multiple devices.