Hi,
We are using 1.x-dev for feeds_xpathparser and 2.x-dev for Feeds.
Currently we are getting this error:
PHP Fatal error: Declaration of FeedsXPathParserBase::sourceFormValidate() must be compatible with that of FeedsSourceInterface::sourceFormValidate()
It looks like the feeds_xpathparser code is using a type hint which isn't in the base interface.