TOKYO, Jan 28 - The Bank of Japan was seen buying dollars against the yen from about 105.80 yen on Wednesday, Tokyo traders said. The dollar suddenly jumped to a high of 106.65 yen shortly after the suspected BOJ action before falling back to 106.07/10 as of 0703 GMT, traders said. A senior currency trader in Tokyo said the central bank appeared to be intervening through several Japanese banks.//