Validation with DTD and MS-Schema

[wxdqz]

I know that it is possible to add a DTD and a schema to an XML.This is interesting for shared XML with groups that will not use MSXML3 (andso do not what to use Microsoft specification).But when validating with MSXML3, witch one has precedance and what happendsif there is a contradictionbetween both specification ?<!-- both DTD ans the MS schema are declared --><!DOCTYPE XMLData SYSTEM "XMLData.dtd"><XMLData xmlns="x-schema:XMLDataSchema.xml">.....