out or inout argument 2 for test mysql is not varibale or new pseudo-variable in befor trigger

 I use Odbc syntax like "{call test( ?, ? )}", and bind the two parameters to SQL_INPUT_PARAM andSQL_OUTPUT_PARAM.
But there is Error like "out or inout argument 2 for test mysql is not varibale or new pseudo-variable in befor trigger" .
please help me.thank you