Keep in mind that the current version of MySQL is in the 5.x versions, 4.x which has been out for several years and over time certain features and functionality has been added; it doens't seem to be asking too much for how certain portions of MySQL work currently... Having to cut back from features in the current versions to support legacy versions is asking a lot, and I think that MySQL3 shouldn't be a logical step to have 110% support for..
