diff --git a/CHANGES b/CHANGES
index 6f35fce..83c5318 100644
--- a/CHANGES
+++ b/CHANGES
@@ -110,6 +110,9 @@ porting:
 	David Arnstein contributed a patch for NetBSD 5.1 including stdbool.h
 	support and appropriate files in Config/
 
+	Lauri Tirkkonen contributed a patch regarding netinet/if_ether.h
+	on Illumos
+
 testing:
 	Do not distribute testcert.conf with socat source but generate it
 	(and new testcert6.conf) during test.sh run.
diff --git a/configure.in b/configure.in
index 8d8fff6..5610f2c 100644
--- a/configure.in
+++ b/configure.in
@@ -297,7 +297,12 @@ if test "$WITH_INTERFACE"; then
   AC_CHECK_HEADER(netinet/if_ether.h,
     AC_DEFINE(HAVE_NETINET_IF_ETHER_H),
     [WITH_INTERFACE=;
-     AC_MSG_WARN([include file netinet/if_ether.h not found, disabling interface])])
+     AC_MSG_WARN([include file netinet/if_ether.h not found, disabling interface])],
+     [AC_INCLUDES_DEFAULT
+     #if HAVE_NET_IF_H && HAVE_NETINET_IN_H
+     #include <net/if.h>
+     #include <netinet/in.h>
+     #endif])
 fi
 if test "$WITH_INTERFACE"; then
    AC_DEFINE(WITH_INTERFACE)