libplist-1.3 build error in plistPYTHON_wrap.cxx

$ cmake [...] [100%] Building CXX object swig/CMakeFiles/plist.dir/plistPYTHON_wrap.cxx.o cd /usr/ports/pobj/libplist-1.3/libplist-1.3/swig && /usr/bin/c++ -D_plist_EXPORTS -O2 -pipe -fPIC -I/usr/ports/pobj/libplist-1.3/libplist-1.3/include -I/usr/local/include/python2.7 -o CMakeFiles/plist.dir/plistPYTHON_wrap.cxx.o -c /usr/ports/pobj/libplist-1.3/libplist-1.3/swig/plistPYTHON_wrap.cxx
/usr/ports/pobj/libplist-1.3/libplist-1.3/swig/plistPYTHON_wrap.cxx: In function 'PyObject _wrap_Date_get_value(PyObject, PyObject)': /usr/ports/pobj/libplist-1.3/libplist-1.3/swig/plistPYTHON_wrap.cxx:9770: error: invalid conversion from 'long int' to 'const time_t' /usr/ports/pobj/libplist-1.3/libplist-1.3/swig/plistPYTHON_wrap.cxx:9770: error: initializing argument 1 of 'tm gmtime(const time_t)' ** Error code 1

The offending line in plistPYTHON_wrap.cxx are:
struct tm* t = gmtime ( &(&result)->tv_sec );

$ swig -version SWIG Version 2.0.4
Compiled with c++ [i386-unknown-openbsd5.0]
Configured options: +pcre

$ g++ -dumpversion 4.2.1