diff --git a/config.h.in b/config.h.in
index 0c9f33059..38b7feec5 100644
--- a/config.h.in
+++ b/config.h.in
@@ -19,6 +19,9 @@
 /* Define as 1 if you have <machine/types.h> */
 #define MACHINE_TYPES_H 0
 
+/* Define as 1 if you have <sys/socket.h> */
+#define MACHINE_SYS_SOCKET_H 0
+
 /* Define as 1 if you have <glob.h> */
 #define HAVE_GLOB_H 0
 
diff --git a/configure.in b/configure.in
index b568f0abe..6e42b25d7 100644
--- a/configure.in
+++ b/configure.in
@@ -218,7 +218,7 @@ dnl Checks for header files we can live without.
 AC_HEADER_STDC
 AC_HEADER_MAJOR
 AC_CHECK_HEADERS(netinet/in_systm.h limits.h)
-AC_CHECK_HEADERS(alloca.h dirent.h)
+AC_CHECK_HEADERS(alloca.h dirent.h sys/socket.h)
 AC_CHECK_HEADERS(machine/types.h string.h)
 AC_CHECK_HEADERS(glob.h,,MISCOBJS="$MISCOBJS glob.o")
 AC_CHECK_HEADERS(fnmatch.h,,MISCOBJS="$MISCOBJS fnmatch.o")
diff --git a/ftp.c b/ftp.c
index a64c930b5..931dfaf2f 100644
--- a/ftp.c
+++ b/ftp.c
@@ -4,6 +4,7 @@
 #define HAVE_MACHINE_TYPES_H 1
 #define HAVE_ALLOCA_H 1
 #define HAVE_NETINET_IN_SYSTM_H 1
+#define HAVE_SYS_SOCKET_H 1
 #endif
 
 #if HAVE_MACHINE_TYPES_H
@@ -14,6 +15,10 @@
 # include <alloca.h>
 #endif
 
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+
 #if HAVE_NETINET_IN_SYSTM_H
 # include <sys/types.h>
 # include <netinet/in_systm.h>
diff --git a/misc/miscfn.h b/misc/miscfn.h
index bd033a067..a0831e715 100644
--- a/misc/miscfn.h
+++ b/misc/miscfn.h
@@ -50,4 +50,8 @@ extern time_t timezone;
 extern void *myrealloc(void *, size_t);
 #endif
 
+#if HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+
 #endif