Finding the maximum depth from a node

Ok, I have basically almost a file structure in an xml document, something
like this:

<root>
	<folder name="1">
		<folder name="2"/>
		<folder name="3">
			<folder name="4"/>
		</folder>
	<folder name="5">
		<folder name="6">
			<folder name="7">
				<folder name="8"/>
			</folder>
		</folder>
	</folder>
</root>

I need to be able to find out how deep the nodes go, i.e. when the template
has matched root, I need to work out how deep the deepest folder is (folder 8
in this case). I know how to calculate a depth from a nodes context, but not
the depth of its children.

Anybody got any ideas. I'm quite new to XSL so chances are I've missed
something obvious, but I have searched the faq and the list archive and found
nothing helpful.

Dave

--
"Nothing is foolproof to a sufficiently talented fool."

Mr. Dave Townsend
Research Engineer
Brass Bullet Ltd
Pemchurch Chambers
30-32 Cradock Street
Swansea
SA1 3EP
Phone:   +44(1792) 417227
Mobile:  +44(7909) 962336
Fax:     +44(1792) 533035
Website: www.brass-bullet.co.uk


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