How do you Generate XML file from 2 oracle tables?

 Hello,

   We are trying to create a PL/SQL procedure that will   get data from a headers and details table.

   Think of it as     Dept (header)  table   and EMP  (details) table.

   We need an xml file  that   will list  all  Employees  under  each department.  Basically it will list the Dept, then all its employees,  then another Dept with all its employees.

  We have created from a single table  an  XML file,  using  XMLELEMENT, XMLAGG, and XMLFOREST.

  Any help is appreciated.

  We are on 10g database.

   jim borror