Search time - xpath command namespace handling

Splunk: 5.0.4

Anyone know how to give the namespace to the xpath command? When looking at the xpath command and other discussions they always speak to simple examples without namespaces.

For example when providing a modified xml from the Splunk examples with a namespace, it justifiably doesn't return a value anymore.

command: | xpath outfield=identity_id "//DataSet/identity_id"

document:

<DataSet xmlns="http://www.w3schools.com/furniture">
        <identity_id>3020</identity_id>
        <instrument_id>912383KM1</instrument_id>
        <transaction_code>SEL</transaction_code>
        <sname>BARC</sname>
        <currency_code>USA</currency_code>
</DataSet>

Any help would be appreciated.