cygwin build fails

Hi,

I'm trying to build log4cxx 0.9.7 on cygwin with gcc 3.3.1 but I get the
following error, any help would be appreciated. I have had no luck
searching through the archives.

g++ -DHAVE_CONFIG_H -I. -I. -I../include/log4cxx -I../include
-I/usr/include/li
bxml2 -D_REENTRANT -g -O2 -MT appenderattachableimpl.lo -MD -MP -MF
.deps/append
erattachableimpl.Tpo -c appenderattachableimpl.cpp  -DPIC -o
.libs/appenderattac
hableimpl.o

In file included from appenderattachableimpl.cpp:17:
../include/log4cxx/helpers/tchar.h: In static member function `static void
  Convert::int64ToString(wchar_t*, unsigned int, const int64_t&)':
../include/log4cxx/helpers/tchar.h:50: error: `swprintf' undeclared
(first use
  this function)

thanks
Pablo.