WASHINGTON (AP) President Bush and Chinese President Jiang Zemin were reviewing drafts of a letter Friday that would have a joint commission resolve a dispute over a U.S. spy plane and its 24-member crew, as the two sides moved toward a diplomatic resolution.With Bush administration optimism rising, Sen. John W. Warner, R-Va., said the formula for a solution was being outlined in the letter. It would give both the Americans and the Chinese an opportunity to air their cases.The proposal is designed to lead to the release of the 24 American crew members held since Sunday by the Chinese. By all accounts, they are being well-treated, but their 6-day detention has roiled an already touchy U.S. relationship with China.