schema for XHTML 1.0

Hello,

the schema for XHTML 1.0 Strict which is linked to from 
http://www.w3.org/TR/xhtml1-schema/ and whose URL is 
http://www.w3.org/2002/08/xhtml/xhtml1-strict.xsd seems to be incorrect.  
XMLmind's XML editor outputs the following validation errors upon loading 
this schema:

	[1]
	cannot derive simpleType by restriction: "([-+]?(\d+|\d+(\.\d+)?%)(,\s*[-+]?
	(\d+|\d+(\.\d+)?%))*)" invalid value for pattern facet: character "-" must be
	escaped with "\" in this context [st-props-correct.1]

	[2]
	cannot derive simpleType by restriction: "([-+]?(\d+|\d+(\.\d+)?%))" invalid
	value for pattern facet: character "-" must be escaped with "\" in this
	context [st-props-correct.1]

	[3]
	cannot derive simpleType by restriction: "([-+]?(\d+|\d+(\.\d+)?%)|[1-9]
	(\d+)?\*)" invalid value for pattern facet: character "-" must be escaped
	with "\" in this context [st-props-correct.1]

What's the reason for this?  Is escaping the - characters enough to get a 
correct schema?

Best wishes,
Wolfgang