For some iPhone users, months of waiting in anticipation for the iPhone 4 and hours of standing in line ended in a big disappointment. Glitches forced some users who had pre-ordered their phones to go home without a device in hand – even though they thought they were eligible for an upgrade.

Glen LaFratte, a Dallas, Texas, iPhone user, is one of them. LaFratte bought two 3G S phones – for him and his wife – last June. He paid the full price of nearly $700 for each phone.

To his surprise, when he reserved a pair of iPhone 4s a week ago, he found his wife's phone was deemed not eligible for the upgrade pricing of $200 for a 16-GB version and $300 for the 32-GB model.

LaFratte says he bought both the 3G S phones on the same day and even showed AT&T store representatives a receipt to prove that. But so far, he hasn't heard back from AT&T with a fix.

"How much blood do they want?" he wrote in an e-mail to Gadget Lab. "Apple needs to dump AT&T. I cannot understand why a huge computer manufacturer like Apple lets a cellular company control their pricing and cripple them."

Apple's iPhone 4 debuted in retail stores Thursday morning to huge crowds. Meanwhile, a number of users are complaining about network reception problems with the device, especially when the left and the bottom of the phone is touched or squeezed.

Apple had said that any current iPhone customers whose contracts were due to expire this year would be eligible for the lower upgrade price of $200 for the 16-GB iPhone 4 and $300 for the 32-GB version.

The problems with the upgrade are not widespread, with just a handful of users reporting the issue to Gadget Lab so far.

Among them is Josh Strom, who handles system support for Wired, who faced a similar baffling upgrade problem.

After waiting in line for two hours, Strom found out his pre-ordered iPhone 4 won't be available for the upgrade price of $200. His current iPhone 3G contract ends this month.

"I am frustrated and really upset with AT&T," says Strom. "They just couldn't tell me why I cannot upgrade my iPhone."

Meanwhile, other AT&T users are discovering that the upgrade pricing may not be for everyone.

At the Apple Worldwide Developers Conference this year, Steve Jobs made an offer that seemed too good to be true.

"I am thrilled to announce that AT&T is going to make an incredibly generous upgrade offer. If your contract expires any time during 2010, you are immediately eligible for a new iPhone 4 at the same $199, $299 prices if you top up your contract for two years. You can get up to six months early eligibility for the iPhone 4," Jobs told the attendees while introducing the phone.

That declaration, though, left out the fine print. Some AT&T users found that unless your current phone is an iPhone, the upgrade offer does not apply, even if you have another smartphone from AT&T.

Another user, Chris Heery, faced a system glitch that froze him out of the reservation system in the store. He'd canceled his pre-order in the hopes of picking up a phone from the store on the day of the launch. Heery says he might now have to wait until the end of this week so AT&T can sort the issue out and give him an iPhone 4.

If you are eligible for an upgrade and have been denied one by AT&T, let us know what happened. Post your experience in the comments.

*Photo: Kevin Aungle yells triumphantly as he exits the Apple store with a 32-GB iPhone 4 in Emeryville on June 24. Aungle slept in his car the night before the new iPhone was launched and says he waited a total of 15 hours. *(Stefan Armijo/Wired.com)