Less than a month after lambasting European Central Bank President Jean-Claude Trichet for failing to keep up with Ben S. Bernanke's efforts to stem the recession, foreign-exchange traders are glad he's behind the curve.

The 16-nation currency strengthened 7.5 percent versus the dollar since February, after tumbling 9.3 percent in the first two months of the year. JPMorgan Chase & Co, Morgan Stanley and Citigroup Inc are advising investors to buy euros.

Traders are looking past forecasts from Germany's Kiel-based IfW institute for the European Union economy to shrink 3.3 percent this year, and snapping up currencies where central bankers are resisting calls to purchase debt securities as a way of lowering interest rates and pump cash into their financial systems. Those options are becoming scarce after Federal Reserve Chairman Bernanke joined the Bank of England, Bank of Japan and Swiss National Bank in so-called quantitative easing.