As Rasmus suggested on the list, I fixed some failing tests, and planning to do more.
https://gist.github.com/973681
the patch should cleanly apply to the 5_3 branch and trunk also.
about the fixes:
ext/standard/tests/file/bug39863.phpt
this is fixed in 5_3, so I removed the XFAIL, but AFAIK TRUNK still has this bug, and this can be a security problem, so I would suggest to fix this asap.
ext/standard/tests/serialize/serialization_objects_001.phpt
ext/standard/tests/serialize/serialization_objects_003.phpt
ext/standard/tests/serialize/001.phpt
ext/standard/tests/serialize/serialization_objects_002.phpt
ext/standard/tests/serialize/serialization_arrays_001.phpt
added a serialize_precision=100 INI entry for these tests
ext/standard/tests/network/gethostbynamel_error.phpt
there was an unnecessary newline between the expected output lines, I removed that, and also removed a newline between the two instruction to make that less confusing.
ext/date/tests/DateInterval_format_a.phpt
added the OS check to the SKIPIF block, that test should only run on Windows.
ext/date/tests/bug51994.phpt
as Felipe suggested on the irc channel, test for existing non-resolved bugs should be marked with XFAIL.
ext/date/tests/bug51819.phpt
same here