The .directory class allows for storing methods with an index. Sending that index as a message to the directory will cause the method to be executed and its return value will be returned.
If one sends the index name to the directory object and supplies arguments, e.g. "dir~some_name(1,2,3)" then these arguments are not passed on to the setmethod'ed method and therefore cannot be retrieved from within the method.
This RFE asks for enhancing the .Directory's UNKNOWN method such, that the invoked method will get those arguments forwarded, such that the method's code can retrieve the arguments via the arg()-bif or the PARSE|USE ARG keyword statements.