Redefine and Import used together - is this valid?

I have the following situation:

1) Base industry standard schema (ACORD)
2) A schema that imports the ACORD schema (to reuse data types and some 
elements) that defines my organizations new elements and aggregates (ACME)
3) A schema that redefines #1 ACORD to modify existing elements and 
aggregates to include my new ACME elements.

I then have a docuemnt instance the references #3.

Xerces and XSV say my document and schemas are valid. When I run this with 
XML Spy I can validate the schemas standalone, but when I try to validate 
the document based upon the schemas, Spy reports that my redefined 
elements in #3 have already been defined and this is an error.

Becasue I knew Spy uses more than one parser (different views use 
different parsers) I figured the parser valdiating the document was 
incorrect. Well the Altova folks say their schema validation is wrong in 
this case. Can I get some confirmation of this one way or another from 
this group?

If Altova is correct then I think the Schema working group has some 
serious work to fix this problem. I'm assuming that I should be able to 
reuse an industry schema in this manner. We want to both use the same 
datatypes from ACORD as well in some places to add ACORD elements into our 
new elements when the definitions are appropriate. If I have to recreate 
all these types and elements, I loose much of that promise of resuability.

Any light you can shed on this situation is much appreciated. Meanwhile 
I'll be tryiing to read the spec on this topic.

...dan

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Danny Vint

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Received on Friday, 15 September 2006 16:19:33 UTC