diff -ur old/libXext-1.0.4/src/extutil.c new/libXext-1.0.4/src/extutil.c
--- old/libXext-1.0.4/src/extutil.c	2007-11-28 01:46:14.000000000 +0100
+++ new/libXext-1.0.4/src/extutil.c	2008-10-09 23:33:07.000000000 +0200
@@ -235,7 +235,7 @@
 
 
 
-static int _default_exterror (Display *dpy, char *ext_name, char *reason)
+static int _default_exterror (Display *dpy, _Xconst char *ext_name, _Xconst char *reason)
 {
     fprintf (stderr, "Xlib:  extension \"%s\" %s on display \"%s\".\n",
 	     ext_name, reason, DisplayString(dpy));
@@ -248,11 +248,11 @@
  * requested extension is referenced.  This should eventually move into Xlib.
  */
 
-extern int (*_XExtensionErrorFunction)(Display*, char *, char * );
+extern XextErrorHandler _XExtensionErrorFunction;
 
-int (*XSetExtensionErrorHandler(int (*handler)(Display*, char *, char * )))(Display*, char *, char * )
+XextErrorHandler XSetExtensionErrorHandler (XextErrorHandler handler)
 {
-    int (*oldhandler)(Display*, char *, char * ) = _XExtensionErrorFunction;
+    XextErrorHandler oldhandler = _XExtensionErrorFunction;
 
     _XExtensionErrorFunction = (handler ? handler :
 				_default_exterror);
@@ -265,8 +265,8 @@
  */
 int XMissingExtension (Display *dpy, _Xconst char *ext_name)
 {
-    int (*func)(Display*, char *, char *) = (_XExtensionErrorFunction ?
-		     _XExtensionErrorFunction : _default_exterror);
+    XextErrorHandler func = (_XExtensionErrorFunction ?
+			     _XExtensionErrorFunction : _default_exterror);
 
     if (!ext_name) ext_name = X_EXTENSION_UNKNOWN;
     return (*func) (dpy, ext_name, X_EXTENSION_MISSING);
diff -ur old/libXext-1.0.4/src/globals.c new/libXext-1.0.4/src/globals.c
--- old/libXext-1.0.4/src/globals.c	2007-11-28 01:47:48.000000000 +0100
+++ new/libXext-1.0.4/src/globals.c	2008-10-09 23:44:56.000000000 +0200
@@ -75,8 +75,7 @@
 /*
  * Error handlers; used to be in XlibInt.c
  */
-typedef int (*funcptr)(Display*, char *, char *);
-ZEROINIT (funcptr, _XExtensionErrorFunction, NULL);
+ZEROINIT (XextErrorHandler, _XExtensionErrorFunction, NULL);
 
 /*
  * NOTE: any additional external definition NEED
diff -ur old/xextproto-7.0.3/Xext.h new/xextproto-7.0.3/Xext.h
--- old/xextproto-7.0.3/Xext.h	2008-05-22 02:05:29.000000000 +0200
+++ new/xextproto-7.0.3/Xext.h	2008-10-09 23:32:59.000000000 +0200
@@ -32,16 +32,14 @@
 
 _XFUNCPROTOBEGIN
 
-extern int (*XSetExtensionErrorHandler(
-    int (*handler)(
-		   Display *,
-		   char *,
-		   char *
-		   )
-))(
-		   Display *,
-		   char *,
-		   char *
+typedef int (*XextErrorHandler) (
+    Display *		/* dpy */,
+    _Xconst char*	/* ext_name */,
+    _Xconst char*	/* reason */
+);
+
+extern XextErrorHandler XSetExtensionErrorHandler(
+    XextErrorHandler	/* handler */
 );
 
 extern int XMissingExtension(