--- libjbig/Makefile
+++ libjbig/Makefile
@@ -1,7 +1,16 @@
 # Options for the compiler: A high optimization level is suggested
 CFLAGS = -O -Wall -ansi -pedantic
 
-all: libjbig.a tstcodec
+AR = ar
+RANLIB = ranlib
+
+ifeq ($(USERLAND),Darwin)
+	SONAME = dylib
+else
+	SONAME = so
+endif
+
+all: libjbig.a libjbig.$(SONAME) tstcodec
 
 tstcodec: tstcodec.c jbig.c jbig.h jbig_tab.o
 	$(CC) $(CFLAGS) -o tstcodec -DTEST_CODEC tstcodec.c jbig.c \
@@ -15,8 +26,17 @@
 
 libjbig.a: jbig.o jbig_tab.o
 	rm -f libjbig.a
-	ar rc libjbig.a jbig.o jbig_tab.o
-	-ranlib libjbig.a
+	$(AR) rc libjbig.a jbig.o jbig_tab.o
+	$(RANLIB) libjbig.a
+
+SOBJS = jbig.lo jbig_tab.lo
+libjbig.so: $(SOBJS)
+	$(CC) -shared $(LDFLAGS) -o $@ -Wl,-soname -Wl,$@ $(SOBJS)
+libjbig.dylib: $(SOBJS)
+	$(CC) -dynamic $(LDFLAGS) -o $@ -dynamiclib -install_name $@ $(SOBJS)
+
+%.lo: %.c jbig.h
+	$(CC) $(CFLAGS) -fPIC -c $< -o $@
 
 jbig.o: jbig.c jbig.h