(FORTUNE Magazine) – Brazil's mighty Amazon River was once a mere trickle of water. So there's reason for Brazilians to be optimistic about a new debt-for-equity swap program that is cutting a small stream of relief through that country's mountainous $121 billion of foreign debt. The new plan has opened up a flow of foreign investment that could help kick-start the country's stalled economy. The first of what will be monthly auctions was held at the Rio de Janeiro Stock Exchange on March 29. Brokers for foreign creditors -- usually banks that had bought troubled Brazilian loans at deep discounts on a secondary market -- bid for the right to exchange the loans for $150 million in cruzeiros to invest in the country. An investor who had acquired a $10 million loan at 60% of face value could try to swap it at, say, 70% of face value and lock in a $1 million profit. By the end of the first day, $187 million in debt had been swapped away. The Sao Paulo stock exchange was the site of a second auction held on April 28. This time another $150 million in cruzeiros was exchanged for $198 million of debt. The success of these two auctions may lead to an increase in the $150 million monthly cruzeiro cap, which would expand the amount of money pouring in from foreign sources. The auctions offer debt holders a cheaper way to capitalize business ventures in the country than is available through direct investment. Arnoldo Wald, president of CVM, Brazil's SEC, says conversion is likely to cancel about $4 billion of debt a year. He also says the Central Bank will soon announce rules allowing foreigners to pay for some Brazilian exports with debt.