+dnl check for vsscanf() and vsnprintf() - on some platforms (Linux, glibc
+dnl 2.1.1 for the first one, HP-UX for the second) it's available in the
+dnl library but the prototype is missing, so we can't use AC_CHECK_FUNCS here,
+dnl do it manually
+
+dnl we use AC_TRY_COMPILE() here instead of AC_TRY_RUN() to make the checks
+dnl work for cross-compilation, but AC_TRY_COMPILE() normally only compiles
+dnl one function while we need at least 2 - hence the ugly hack below. To
+dnl understand why it works, remember that AC_TRY_COMPILE() just prepends
+dnl "int main() {" in the beginning of the code and "; return 0; }" at the
+dnl end...
+
+dnl if we fail to find vsnprintf, also try for _vsnprintf as that is what
+dnl we'll find under MSW if it exists.
+
+dnl final note: AC_TRY_COMPILE will only be executed if there is nothing in
+dnl the cache so we have to do AC_DEFINE(HAVE_VSNPRINTF) below and not inside
+dnl it or the symbol wouldn't be defined for the 2nd and subsequent configure
+dnl runs
+
+dnl check for vsnprintf() - a safe version of vsprintf()
+AC_CACHE_CHECK([for vsnprintf], wx_cv_func_vsnprintf,