Jean-Baptiste Clot found a bug in the timeZoneCFC concerning the inDST function (tells you whether a date is in daylight savings time. it was one of those java bah humbugs. the CFC makes use of a gregorian calendar object (the original java one not ICU4J) where MONTHs are zero-based, that is january is 0. btw the other fields in that object aren't zero-based and that's my excuse for this one. i was constructing the calendar object using year, month, day, hour, minute pulled from the argument date by equivalent cf function where months aren't zero-based. so the dates that were actually being tested were one month in the future.
its fixed and you can find the testbed here. the file in the devnet gallery will be available soon, in the meantime you can find the fixed CFC here .