Constellation Energy Partners LLC, Baltimore, (NYSE: CEP) plans to acquire certain coalbed-methane properties in the Cherokee Basin in Oklahoma from Newfield Exploration Mid-Continent Inc., a subsidiary of Newfield Exploration Co., Houston, (NYSE: NFX) for $128 million. The assets include an average 94% working interest in more than 650 producing wells on approximately 80,000 net acres. Net production is 10 million cubic feet of gas equivalent. Proved reserves are 45 billion cubic feet of gas equivalent. The assets also include a 350-mile gas-gathering system.