"Validate twice with surgery" is the informal name of a technique
which will do exactly what you are looking for.
There's a writeup of a talk about this from XML Europe 2004 available
[1], and a free demo of a pipeline-based implementation which you can
try with your own document and schema [2].
ht
[1]
http://www.markup.co.uk/XMLEu2004/
[2]
http://www.markup.co.uk/showcase/
--
Henry S. Thompson, Markup Technology Ltd.
4 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- +44 (0) 7866 471 388
Fax: (44) 131 650-4587, e-mail:
ht@markuptechnology.com
URL:
http://www.markup.co.uk/
[mail really from me _always_ has this .sig -- mail without it is forged spam]