diff -Naur libdkim.orig/src/Makefile libdkim/src/Makefile
--- libdkim.orig/src/Makefile	2009-03-17 17:06:24.000000000 -0500
+++ libdkim/src/Makefile	2009-03-17 17:07:12.000000000 -0500
@@ -1,15 +1,10 @@
 # libdkim makefile for UNIX
 #
 
-#ifdef LINUX
-CFLAGS  = -c
-LFLAGS  = 
+DESTDIR ?= /
+
+CFLAGS  += -fPIC
 LIBS    = -lcrypto -lresolv
-#else
-CFLAGS  = -c
-LFLAGS  = 
-LIBS    = -lcrypto 
-#endif
 
 INCL	=  -I /usr/include/openssl/
 
@@ -19,23 +14,34 @@
 
 HDRS = dkim.h dns.h dkimbase.h dkimsign.h dkimverify.h
 
-all: libdkim.a libdkimtest
+all: libdkim.so.1 libdkimtest
 
 libdkim.a: $(OBJS)
 	rm -f libdkim.a
 	ar cr libdkim.a $(OBJS)
 	ranlib libdkim.a
 
-libdkimtest : libdkim.a libdkimtest.o
-	g++ -olibdkimtest $(LFLAGS) \
-	       -L . libdkimtest.o $(LIBS) -ldkim
+libdkim.so.1: $(OBJS)
+	$(CXX) -shared -Wl,-soname,$@.1 $(LDFLAGS) $(OBJS) -o $@ $(LIBS)
+	ln -s $@ libdkim.so
+
+.cpp.o:
+	$(CXX) $(CFLAGS) -c $<
+
+libdkimtest : libdkim.so.1 libdkimtest.o
+	$(CXX) -o$@ $(LDFLAGS) \
+	       -L. libdkimtest.o $(LIBS) -ldkim
 	
 libdkimtest.o: libdkimtest.cpp $(HDRS)
 
-.cpp.o:
-	g++ $(CFLAGS) -c $<
 
 clean:
-	rm  *.o libdkim.lib libdkimtest
+	rm -f *.o libdkim.{a,so,so.1} libdkimtest
+
+install: all
+	install -D -m 0755 libdkim.so.1 $(DESTDIR)/usr/lib/libdkim.so.1
+	ln -s libdkim.so.1 $(DESTDIR)/usr/lib/libdkim.so
+	install -D -m 0644 dkim.h $(DESTDIR)/usr/include/dkim.h
+	install -D -m 0755 libdkimtest $(DESTDIR)/usr/bin/libdkimtest
 
 
diff -Naur libdkim.orig/src/dkim.h libdkim/src/dkim.h
--- libdkim.orig/src/dkim.h	2009-03-17 17:06:24.000000000 -0500
+++ libdkim/src/dkim.h	2009-03-17 17:06:53.000000000 -0500
@@ -22,7 +22,6 @@
 #define DKIM_CALL	WINAPI
 #else
 #define DKIM_CALL
-#define MAKELONG(a,b) ((long)(((unsigned)(a) & 0xffff) | (((unsigned)(b) & 0xffff) << 16)))
 #endif
 
 
@@ -162,6 +161,32 @@
 
 char *DKIM_CALL DKIMGetErrorString( int ErrorCode );
 
+#ifndef _WIN32
+/*
+ * macros.h:  Useful macros
+ *
+ * Author:
+ *	Dick Porter (dick@ximian.com)
+ *
+ * (C) 2002 Ximian, Inc.
+ */
+#ifndef _WAPI_MACROS_H_
+#define _WAPI_MACROS_H_
+
+#include <sys/types.h>
+
+#define MAKEWORD(low, high) ((__uint16_t)(((__uint8_t)(low)) | \
+				       ((__uint16_t)((__uint8_t)(high))) << 8))
+#define MAKELONG(low, high) ((__uint32_t)(((__uint16_t)(low)) | \
+				       ((__uint32_t)((__uint16_t)(high))) << 16))
+#define LOWORD(i32) ((__uint16_t)((i32) & 0xFFFF))
+#define HIWORD(i32) ((__uint16_t)(((__uint32_t)(i32) >> 16) & 0xFFFF))
+#define LOBYTE(i16) ((__uint8_t)((i16) & 0xFF))
+#define HIBYTE(i16) ((__uint8_t)(((__uint16_t)(i16) >> 8) & 0xFF))
+
+#endif /* _WAPI_MACROS_H_ */
+#endif
+
 #ifdef __cplusplus
 }
 #endif
diff -Naur libdkim.orig/src/dkimsign.cpp libdkim/src/dkimsign.cpp
--- libdkim.orig/src/dkimsign.cpp	2009-03-17 17:06:24.000000000 -0500
+++ libdkim/src/dkimsign.cpp	2009-03-17 17:06:53.000000000 -0500
@@ -25,8 +25,6 @@
 #else
 #define _strnicmp strncasecmp 
 #define _stricmp strcasecmp 
-#define LOWORD(l) ((unsigned)(l) & 0xffff)
-#define HIWORD(l) ((unsigned)(l) >> 16)
 #endif
 
 #include <string.h>