xs:any and Validation

Can anyone help me out by clarifying what the correct behavior should be for an XSD validator in the prescence of xs:any?

Imagine I had the following schema:

<?xml version="1.0" encoding="utf-8" ?>
<xs:schema
targetNamespace="http://www.winterdom.com/schemas/valprb1"
elementFormDefault="qualified"
xmlns="http://www.winterdom.com/schemas/valprb1"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
>
<xs:element name="test">
<xs:complexType>
<xs:sequence>
<xs:element name="value1" type="xs:string"/>
<xs:any namespace="##any" processContents="skip" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>

And the following XML:

<test xmlns="http://www.winterdom.com/schemas/valprb1">
<value1>whatever</value1>
<!-- Should fit in xs:any -->
<s:other xmlns:s="http://www.winterdom.com/schemas/other">asdad</s:other>
</test>

What should the correct behavior be here regarding the validation of s:other given my specification of processContents="skip"? I'm not quite entirely sure of what the XSD specification implies. My initial understanding would've been that the validator should not try to actually validate anything fitting in the xs:any section, just verify that it is indeed valid XML. However, this seems not to be the case, at least for the .NET XmlValidatingReader, which reports:

Error: Could not find schema information for the
element 'http://www.winterdom.com/schemas/other:other'.
An error occurred at file:///C:/temp/test.xml(4, 5).

The message obviously points out that I haven't given any schema information for s:other, but my question goes towards the why I should have to do it? If I was using skip?

So I'm probably misunderstanding how things are supposed to work, and I'd love it if someone would point me out in the right direction...