fn-lang-15 expects FOTY0011, but the way it is currently written we believe 
that XPTY0019 (It is a type error if the result of a step (other than the last 
step) in a path expression contains an atomic value) is correct.

The test is currently as follows:

  for $x in (1)
    return $x/fn:lang("en-us")

We believe it would be better to write this test as follows

  1[fn:lang("en-us")]

This will test error condition FOTY0011

Thanks,
Marc