Are XML tools good enough to use in life-critical applications?

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

Are you using XML in life-critical applications such as controlling nuclear power plants or controlling aircraft flight systems? 

Can I rely on an XPath query engine to always return the correct results when given a valid XPath query and a well-formed XML document? Is it possible to quantify or bound the correctness of an XPath query engine? Are there XPath query engines that limit the probability of getting an incorrect result to 10**(-9)?

/Roger