this might be helpful, as it took quite some time for me to find this out:
if you're using some .wsdl and there's a sequence that can be there more than once (ie: maxOccurs > 1), you can specify an non-associative array for it if you have more than 1 items OR you could just specify the one item if there is only one:
<?php
'items' => array(
array(
'itemId' => 5,
'name' => 'some name',
),
array(
'itemId' => 6,
'name' => 'some other name',
),
),
?>
this also works:
<?php
'items' => array(
'itemId' => 5,
'name' => 'some name',
),
?>