REFILE-With IMF nod, industry body IFSB to tighten Islamic finance guidance

(Corrects spelling in last two paragraphs)By Bernardo VizcainoMay 29 (Reuters) - The Islamic Financial Services Board (IFSB) will expand its guidance for national regulators after the International Monetary Fund (IMF) adopted its standard for Islamic banking, hastening efforts to harmonise business practices.Islamic finance is now of significant size to be considered systemically important in over