Potash Share Buyback - Best use of Money?

On Thursday, Potash Corporation announced that it will increase its stock repurchase program to up to 10% of the shares outstanding at this time. First, let's note that a planned stock repurchase program does not necessarily mean a single share will be repurchased. The company can repurchase the shares at whatever target price they may have decided. The question is, if I were a shareholder (which I'm not, and I have no position in this company), is this the best plan for the company?

I certainly don't believe this makes the most sense for the company. First of all, the company would need $5b cash based on current market capitalization to buy back 10% of the company. the company only has about $250m cash according to its last quarterly report (as per Google finance). This shows that, in order for the company to complete this repurchase program, at current prices, they would need to borrow the funds to buy the shares off the market. Therefore, current shareholders would basically be mortgaged to buy the selling shareholders. The cost of such a move could be tremendous. The company would essentially be buying shares and leveraging the company in the process - what shareholder or bondholder would want such a move to take place?

Finally, I take an issue, as a value investor, to this type of transaction for any company - if the company is a growth company, and the belief in the market is that Potash is, then shouldn't the company use its cash proceeds to continue to build or purchase the capital infrastructure necessary to mine more potash out of the ground, and increase revenues? If not, why should the stock price be maintained at this level, and why shouldn't all shareholders benefit immediately from the company's apparent success? In my opinion, the best use of funds in a growth company, if it has no better use of funds (when it has excess cash - which Potash doesn't even have) would be to pay a special cash dividend for all current shareholders, rather than mortgaging the current shareholders for the ones exiting from the company. Only time will tell if this move by Potash bears the fruit that the board and CEO intend for it to do.