Pre-MKD argument handling problem (io bug?)

[esmandil]

There seems to be a problem with the way ioFTPD handles arguments in some events. For a one line bat script esmTest.bat:
@echo 550 1: %1 2: %2 3: %3 4: %4 5: %5

[FTP_Pre-Command_Events]
mkd = EXEC ..\scripts\esmTest.bat

(15:23:49) MKD aa bb cc
(15:23:50) 550 1: MKD 2: aa 3: bb 4: cc 5:

The same thing works fine for:

[Events]
OnNewDir = EXEC ..\scripts\esmTest.bat

(15:24:34) MKD aa bb cc
(15:24:35) 550-550 1: "c:\_ftp\upload\aa bb cc" 2: "/upload/aa bb cc" 3: 4: 5:

Anybody knows any workaround? How can I get directory name which can contain spaces in Pre-MKD event?