Can multiple inline schemas have same targetNamespace?

I would appreciate it if you could address the following issue that I have seen in WSDLs of 2 customers in the past month.

One vendor's SOAP stack is creating WSDLs with multiple inline schemas that have the same namespace.

Here's an example:
<wsdl:definition>
<wsdl:types>
<xs:schema targetNamespace="a">
types and elements
</xs:schema>
<xs:schema targetNamespace="a">
different types and elements
</xs:schema>
<xs:schema targetNamespace="b">
whatever
</xs:schema>
</wsdl:types>
...
<wsdl:definition> 

It's not clear to me whether the above is legal or not (two schemas with the same targetNamespace="a").  Should XML parsers for WSDL be smart enough to handle the above?  Or should parsers report errors?  

--
Jeehong Min
Software Engineer
SOAPtest Development
Parasoft Corporation

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