China posted surprisingly weak foreign trade growth in April, signaling that the world\'s second largest economy continues to face strong head winds, both from abroad and at home. The data disappointed markets, coming just as some economists had begun seeing tentative signs in manufacturer surveys and auto sales of a re-acceleration from a three-year low in growth in the first quarter. Several analysts on Thursday called for Beijing to take additional measures to stimulate the economy, including additional spending on public works. Exports rose 4.9% from a year earlier in April, down from 8.9% in March and below economist expectations.