The specter of round-trip trading, which is the practice of pairing symmetrical transactions to boost revenue that has haunted the energy industry for the past six months, reportedly could be lurking in the books of media giant AOL Time Warner ( AOL). Federal prosecutors and the Securities and Exchange Commission are looking into round trip or "back-to-back" deals at AOL's America Online division, according to The Wall Street Journal. Most of the deals are the brainchild of recently departed AOL executive David Colburn, the story said. The probe, which follows AOL's disclosure last week that it was reviewing $49 million in transactions at America Online over several years, will probably be pursued by the SEC, which has a lesser burden in proving AOL tried to deceive investors by not properly disclosing its transactions. AOL is among a handful of companies whose purportedly certified financial statements are being reviewed by the SEC. The agency said it will withhold judgment on AOL, which filed its results and disclosed its internal probe late Wednesday.