ASP.Net, MySQL, and dates

When I read in dates, to ADO.Net datasets, the date gets converted from the
yyyy-mm-dd format to a short date and time field. It's easy enough to
reformat for output using the format function, but even if I just read a
dataset and write it right back, I get null values in the date field. MySQL
will write the record, but once I read it back again, I get a Null error on
the date field. What is actually in the field is 0000-00-00. So, it
doesn't actually get converted before the insert into the table.