Issues with retrieving the last page of archived message

I have monitoring plug in installed. As per

http://xmpp.org/extensions/xep-0059.html#last

I am sending

<iq type='get' id='archive_request'>

<retrieve xmlns='urn:xmpp:archive'

with='user@domain'>

<set xmlns='http://jabber.org/protocol/rsm'>

<max>10</max>

<before/>

</set>

</retrieve>

</iq>

But it always sends the first page.If I set a value like <before>8</before> it sends the items correctly but then I need to make an additional call to get the total count which I dont want to do.

Is there something that I am missing?

Thanks,

Sujith