The way errors were being handled in submit_rpc_handler.php,
the replies could end up looking like:
<error>
...
</error>
<actual_reply>
...
</actual_reply>
which doesn't parse with PHP's simplexml because there's no outer element.
So the PHP interface to job submission didn't work in some cases.
To fix this, I changed the RPC replies to have an enclosing element,
which is the name of the RPC, e.g.
<submit_batch>
<error>
...
</error>
... other stuff
</submit_batch>
RPC replies should now always be valid XML, errors or not.
David Anderson