WASHINGTON (Reuters) - The U.S. Senate signed off Tuesday on a bill that would outlaw the most annoying forms of junk e-mail and create a "do not spam" registry, bringing the first national anti-spam law one step closer to reality. Online marketers who flood e-mail in boxes with pornography and get-rich-quick schemes would face jail time and multimillion-dollar fines under the measure, which passed by a voice vote. The bill has now passed both chambers of Congress, but the House of Representatives must still approve minor technical changes before sending it to the White House, Senate aides said. President Bush...