Did you specify a DATEFORMAT in your servers DSM OPT file?
I think the dateformat of the RESTORE command has to be in the
same format.
*---------------------------------------------------------------*
*  Date format to use.
*               1 = MM/DD/YYYY  (default)
*               2 = DD-MM-YYYY
*               3 = YYYY-MM-DD
*               4 = DD.MM.YYYY
*               5 = YYYY.MM.DD
*---------------------------------------------------------------*

Kind regards
Thomas Rupp
UIS- Informatik Services
Vorarlberger Illwerke AG
MAIL:   thomas.rupp AT illwerke DOT at
TEL:    ++43/5574/4991-251
FAX:    ++43/5574/4991-820-8251