SQL_DATE probably still needs to be quoted. I do not know in MySQL specifically but in PostgreSQL when you send a date in a query it has to be quoted. SQL_INTEGER will tell DBI not to quote it (in PgSQL) and I would think everywhere else so it will work. It does seem kind of 'workaroundish' (makes up a word) though. Maybe a comment to that effect?

The only other way that comes to mind quickly (which isn't as efficient, unless you do lots of inserts and want the same date) would be to select Now() and save the properly formatted 'now' and use that string for inputs which would be quoted.