diff --git a/wmail/configure.ac b/wmail/configure.ac
index 644b9d0..5d79797 100644
--- a/wmail/configure.ac
+++ b/wmail/configure.ac
@@ -14,6 +14,7 @@ PKG_CHECK_MODULES([dockapp], [dockapp])
 
 dnl Checks for header files.
 AC_HEADER_DIRENT
+AC_HEADER_STDBOOL
 AC_HEADER_STDC
 AC_CHECK_HEADERS([limits.h strings.h sys/time.h])
 CPPFLAGS_old="$CPPFLAGS"
diff --git a/wmail/src/common.h b/wmail/src/common.h
index 02385c8..af3a49b 100644
--- a/wmail/src/common.h
+++ b/wmail/src/common.h
@@ -59,11 +59,20 @@
 ///////////////////////////////////////////////////////////////////////////////
 // typedefs
 
-#if !defined(__cplusplus) && !defined(c_plusplus)
-typedef enum {
-    false = 0,
-    true = 1
-} bool;
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# ifndef HAVE__BOOL
+#  ifdef __cplusplus
+typedef bool _Bool;
+#  else
+#   define _Bool signed char
+#  endif
+# endif
+# define bool _Bool
+# define false 0
+# define true 1
+# define __bool_true_false_are_defined 1
 #endif
 
 
diff --git a/wmail/src/config.c b/wmail/src/config.c
index 6a523b9..023869a 100644
--- a/wmail/src/config.c
+++ b/wmail/src/config.c
@@ -497,7 +497,7 @@ static bool ReadEnum( const char *from, unsigned int line, int *to,
 
 static bool IsWhiteSpace( const char *chr )
 {
-    return ( chr != NULL && ( *chr == ' ' || *chr == '\t' || *chr == '\n' )) ? true : false;
+    return chr != NULL && ( *chr == ' ' || *chr == '\t' || *chr == '\n' );
 }
 
 static const char *SkipWhiteSpaces( const char *str )