PHPUnit and MySQL truncation error

I am getting a headache with PHPUnit's behavior of always running TRUNCATE prior to inserting fixtures without first setting foreign key checks off:

Syntax error or access violation: 1701 Cannot truncate a table referenced in a foreign key constraint

Basically, PHPUnit tries to truncate a table before it inserts fixtures. How do I tell it to SET FOREIGN_KEY_CHECKS=0;?