DELETE FROM "database"."schema"."table"
WHERE "id"=123 AND "datetimecolumn"='21/11/2014 00:00:00'
This raises the following error:
"SQL error (3621): The conversion of a char data type to a datetime data type resulted in an out-of-range datetime value. The statement has been terminated."
This also happens when trying to import another HeidiSQL SQL export. Looks like the general handling of DATETIME values for MS-SQL is wrong.