XSD schema load failure

The following schema causes parser exception "mismatched type in MergeRanges":

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
<xs:simpleType name="MediaDesc">
<xs:restriction base="xs:string">
<xs:pattern value="(\s*[^,])*"/>
</xs:restriction>
</xs:simpleType>
</xs:schema>

Note that if I remove \s* from pattern, schema loaded without errors.