Unlocked iPhone 2G on AT&T GoPhone PrePaid Plan using GoPhone's SIM card...Possible?

[Kirley]

Here's the deal. I am getting an unlocked iphone next week. I own a prepaid AT&T GoPhone which has a sim card. AT&T gives you the choice of having a prepaid plan without annual contracts which withdraws the amount of the plan you chose automatically from your debit, credit card, whatever.... So I am thinking, If I activate this prepaid plan on my gophone, then put the SIM card on my unlocked iphone 2g edge, will it work? Will I have a Pre Paid iPhone without annual contracts but with a monthly payment that allows me to do the same stuff contract users do? This is a link to the available plans for gophones they have http://www.wireless.att.com/cell-phone-service/cell-phone-plans/pyp-cell-phone-plans.jsp?wtSlotClick=1-00166N-0-1&WT.svl=calltoaction&_requestid=363734 I am jus wondering, if this works, that would be the greatest thin on earth! By the way, I KNOW that the unlocked iphones works with at&t prepaid phone's sim card, but my concern is, after activiating the particular gophone to this monthly plan, will it work on the iphone? or is it strict to the $14.99 stupid prepaid phone? PLEASE HELP ME OUT. I don't want to buy the iphone and make the worst mistake of my life.