This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
For implementations that have pre-defined the xdt namespace (the spec allows this), K-SeqExprInstanceOf-56 will result in XPST0051. Given the xdt history it is not unlike that a number of implementations wil behave like this. Thanks, Marc
*** This bug has been marked as a duplicate of bug 3353 ***