Fix an issue related to mktime(3) returning -1 when tm_isdst is true but the
timestamp cannot be represented. Previously, -1 was interpreted as a valid
result leading erlang:localtime_to_universaltime/2 to return {{1969, 12, 31},
{23, 59, 59}}.
A detailed explanation may be found here:
http://www.erlang.org/pipermail/erlang-bugs/2008-November/001077.html
Obtained from: Paul Guyot <pguyot at kallisys.net>