diff -ru xproto-7.0.19.orig/Xpoll.h.in xproto-7.0.19/Xpoll.h.in
--- xproto-7.0.19.orig/Xpoll.h.in	2010-11-08 08:35:48 +0100
+++ xproto-7.0.19/Xpoll.h.in	2010-11-08 08:45:04 +0100
@@ -151,7 +151,7 @@
         }
 
 #else /* USE_POLL */
-#include <sys/poll.h>
+#include <@USE_POLL_HEADER@>
 #endif /* USE_POLL */
 
 #else /* WIN32 */
diff -ru xproto-7.0.19.orig/configure.ac xproto-7.0.19/configure.ac
--- xproto-7.0.19.orig/configure.ac	2010-11-08 08:35:47 +0100
+++ xproto-7.0.19/configure.ac	2010-11-08 08:44:48 +0100
@@ -44,7 +44,7 @@
 	[WIDEPROTO=$enableval], [WIDEPROTO=auto])
 
 
-AC_CHECK_HEADERS([sys/select.h sys/param.h sys/types.h sys/time.h])
+AC_CHECK_HEADERS([sys/select.h sys/param.h sys/types.h sys/time.h sys/poll.h poll.h])
 
 # Handle Xpoll.h.in
 # Avoid determining fds_bits on WIN32 hosts (not including cygwin)
@@ -104,6 +104,20 @@
 
 AC_SUBST([USE_FDS_BITS])
 
+# Handle poll.h include from Xpoll.h. don't rely on configure checks
+# performed by other packages, and thus subst the correct header in.
+AC_MSG_CHECKING([poll.h to include])
+
+USE_POLL_HEADER="sys/poll.h"
+if test "x$ac_cv_header_sys_poll_h" != xyes; then
+    if test "x$ac_cv_header_poll_h" = xyes; then
+        USE_POLL_HEADER="poll.h"
+    fi
+fi
+
+AC_MSG_RESULT([$USE_POLL_HEADER])
+AC_SUBST([USE_POLL_HEADER])
+
 
 # Handle Xfuncproto.h
 AC_MSG_CHECKING([whether const prototypes are supported])