xmlrpc question

[eluser]nigelb[/eluser]
I am trying to submit the following information to the XMLRPC server, basically it will be order information and then an array of the Products that make up the order.

I am working with the following code but am getting stuck a variety of error messages such as " htmlspecialchars() expects parameter 1 to be string, array given"

Code:

$request = array(
                   array(
                      // Param 0
                      array('totalOrder'=>10),'struct'),
                       array(
                             // Param 1
                             array(array('productcode'=>1010,'shape'=>'round'),
                                   array('productcode'=>1010,'shape'=>'round')),
                             'struct'
                       )
              );

Anyone got any idea how I can submit the product information as an array.