--- inetutils-1.4.2+20040207.old/configure.ac	Thu Nov  4 03:00:54 2004
+++ inetutils-1.4.2+20040207/configure.ac	Thu Nov  4 02:58:20 2004
@@ -345,18 +345,28 @@
 else
   working_icmp6=yes
 
-  AC_CHECK_HEADER(netinet/icmp6.h, , working_icmp6=no)
+  AC_CHECK_HEADER(netinet/icmp6.h, , working_icmp6=no, [#include <sys/types.h>
+                                                        #include <netinet/in.h>
+                                                        ])
 
   if test "X$working_icmp6" = "Xyes"; then
-    AC_CHECK_HEADER(netinet/ip6.h, , working_icmp6=no)
+    AC_CHECK_HEADER(netinet/ip6.h, , working_icmp6=no, [#include <sys/types.h>
+                                                        #include <netinet/in.h>
+                                                        ])
   fi
 
   if test "X$working_icmp6" = "Xyes"; then
-    AC_CHECK_TYPE(struct icmp6_filter, , working_icmp6=no, [#include <netinet/icmp6.h>])
+    AC_CHECK_TYPE(struct icmp6_filter, , working_icmp6=no, [
+        #include <sys/types.h>
+        #include <netinet/in.h>
+        #include <netinet/icmp6.h>])
   fi
 
   if test "X$working_icmp6" = "Xyes"; then
-    AC_CHECK_TYPE(struct icmp6_hdr, , working_icmp6=no, [#include <netinet/icmp6.h>])
+    AC_CHECK_TYPE(struct icmp6_hdr, , working_icmp6=no, [
+        #include <sys/types.h>
+        #include <netinet/in.h>
+        #include <netinet/icmp6.h>])
   fi
 
   if test "X$working_icmp6" = "Xyes"; then