diff --git a/ChangeLog b/ChangeLog
index f3d3fa667a6b1befa3d75be345be49fa323c9060..d4edc961098b11c6370c7b8fdfb3ff92192befb3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -235,7 +235,8 @@ CVS code -
 	  obsolete and it defines a struct termio that we don't use
 	  anywhere. (DLR)
 	- Typo fixes. (DLR)
-	- Add checks for iswblank(), mblen(), and wctype.h. (DLR)
+	- Add checks for iswalnum(), iswblank() or iswspace(), mblen(),
+	  and wctype.h. (DLR)
 - doc/faq.html:
 	- Remove now-inaccurate note about verbatim input's not working
 	  at prompts, and update its description to mention that it
diff --git a/configure.ac b/configure.ac
index 399840c627dc22d98a5a9fdca8b623a351727676..ba1a2b316cf1e3aca9e62b7fffbac25a7f5bb4b4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -291,7 +291,7 @@ AC_MSG_WARN([*** Can not use slang when cross-compiling])),
     esac], [AC_MSG_RESULT(no)])
 
 dnl Checks for functions
-AC_CHECK_FUNCS(snprintf vsnprintf isblank iswblank strcasecmp strncasecmp strcasestr strnlen getline getdelim mblen mbtowc wctomb wcwidth)
+AC_CHECK_FUNCS(snprintf vsnprintf isblank iswalnum iswblank iswspace strcasecmp strncasecmp strcasestr strnlen getline getdelim mblen mbtowc wctomb wcwidth)
 if test "x$ac_cv_func_snprintf" = "xno" -o "x$ac_cv_func_vsnprintf" = "xno"
 then
 	AM_PATH_GLIB_2_0(2.0.0,,
@@ -357,9 +357,9 @@ then
 	LDFLAGS="$LDFLAGS $GLIB_LIBS"
 fi
 
-if test "x$CURSES_LIB_WIDE" = "xyes" -a "x$ac_cv_func_mblen" = "xyes" -a "x$ac_cv_func_mbtowc" = "xyes" -a "x$ac_cv_func_wctomb" = "xyes" -a "x$ac_cv_func_wcwidth" = "xyes"
+if test "x$CURSES_LIB_WIDE" = "xyes" -a "x$ac_cv_func_iswalnum" = "xyes" -a "x$ac_cv_func_mblen" = "xyes" -a "x$ac_cv_func_mbtowc" = "xyes" -a "x$ac_cv_func_wctomb" = "xyes" -a "x$ac_cv_func_wcwidth" = "xyes" && test "x$ac_cv_func_iswspace" = "xyes" -o "x$ac_cv_func_iswblank" = "xyes"
 then
-	AC_DEFINE(NANO_WIDE, 1, [Define this if your system has wide character support (a wide curses library, mblen(), mbtowc(), wctomb(), and wcwidth()).])
+	AC_DEFINE(NANO_WIDE, 1, [Define this if your system has sufficient wide character support (a wide curses library, iswalnum(), iswspace() or iswblank(), mblen(), mbtowc(), wctomb(), and wcwidth()).])
 else
 	AC_MSG_WARN([Insufficient wide character support found.  nano will not be able to support UTF-8.])
 fi