Sort by foreign date column

I have table with date type column:

chdate date;

SELECT chdate from mytable;

chdate
1999-01-02

But in Russia we have the next date format: DD-MM-YYYY.

When I do coversion to char in SELECT:
TO_CHAR(chdate,'DD-MM-YYYY') everything is ok, but sort by this column
executes as sort for char type.

How can I display my native date format and do right sorting by this column?

--
with respection Andrey Feofilactovich.
e-mail: feo(at)ttn(dot)ru, feo(at)feo(dot)org(dot)ru
ICQ: 28073807