The 5th paragraph in section 3.14 (Importing Schema Components) reads:

"If the xsl:import-schema element contains an xs:schema element, then the schema-location attribute must be absent, and the namespace attribute must either have the same value as the targetNamespace attribute of the xs:schema element (if present), or must be absent, ... "

What is the error code if the namespace attribute and the targetNamespace attribute does not have the same value?

This section of the spec contains one error code which I believe does not apply:

[ERR XTSE0220] It is a static error if the synthetic schema document does not satisfy the constraints described in [XML Schema Part 1] ...