--- np2/x11/configure.ac	2012/01/31 22:07:53	1.26
+++ np2/x11/configure.ac	2012/02/03 13:20:05	1.27
@@ -4,7 +4,7 @@ dnl
 
 dnl require autoconf 2.59
 AC_PREREQ(2.59)
-AC_REVISION($Revision: 1.26 $)
+AC_REVISION($Revision: 1.27 $)
 
 AC_INIT(Xnp2,0.83-20120201,nonakap@gmail.com,xnp2)
 AM_INIT_AUTOMAKE([no-define no-dist no-installinfo subdir-objects])
@@ -42,6 +42,7 @@ AC_STRUCT_TM
 AC_C_VOLATILE
 AC_CHECK_TYPES([ptrdiff_t])
 AC_SYS_LARGEFILE
+AC_C_CHAR_UNSIGNED
 
 dnl
 dnl Check GCC