The way warrants usually work is the company gets the money and pays interest on it. In addition they get warrants to convert the principal into stock in the future at a fixed price. The thinking is that they wouldn't do the conversion unless the stock price is above the trigger level.
I don't know if there are usually provisions for the loan to be paid off, but it is usually more favorable for the company to use the proceeds to expand their business and if they get their valuation to the trigger price then there is some dilution as the debt is converted to stock (but the debt obligation is also removed).
There is probably a default condition also where the debt is converted to stock automatically if the interest payments aren't made (or other conditions are not met) - basically this is a wash-out and the gov't ends up owning the entire company. Similar to BK put pre-determined and will not be triggered if the company performs.
In this way the gov't gets some more bang for their money. They get the interest, and they get a gain on the stock if the trigger level is reached. There are probably some incentives for the company to do this quickly. Also, if AIG fails to perform then the gov't gets the company (not all of it, but most of it).
Are you sure that the warrants are returned after the loan is paid back or does the government get to excercise them. This is the key issue in understanding if we have anything here. Does anyone know ? Thanks.