Jefferies quarterly profit jumps on deal surge, equities trading strength

Sept 28 (Reuters) - Jefferies Financial posted an increase in third-quarter profit on Monday as higher fees from advising on deals and underwriting stock sales were complemented by a record haul in equities trading business.Its results are closely watched on Wall Street for an early glimpse into quarterly investment banking trends, before large US banks report earnings in the coming weeks.Here are some other details:* Global dealmaking has crossed $4 trillion this year as corporate boardrooms look past market volatility…