Even as iPad2 continues to be a complete sell out, Apple is facing another problem. It is so because it facing a crisis as far as maintaining stocks for its 16GB Wi-Fi iPads. These are being sold online, at a discounted rate and are the first-generation of iPad.

The levels are so low that Apple was forced to stop the sale of Apple Online Store's Wi-Fi version of the original iPads. As of now, all of the last year's 3G iPad models are in the clearance section of Apple. They are being priced in between $529, $629 and $729 for iPads carrying 16GB, 32GB and 64GB respectively.

Apple had started offering discounted version of iPad soon after it released iPad2. The unopened iPads are being sold for a discount of $100 while the models that have been refurbished are being sold for $170.

That is not all, in another offer Apple was offering either $100 as refund to the customers who had bought first-generation of iPad in a matter of just 14 days when the iPad 2 announcement was made.