diff --git a/library/Mmakefile b/library/Mmakefile
index 53e0b0bf9..40db01f11 100644
--- a/library/Mmakefile
+++ b/library/Mmakefile
@@ -272,18 +272,23 @@ java_symlinks:
 
 JARS = $(STD_LIB_NAME).jar $(RT_LIB_NAME).jar
 
+# We list the classes in a temporary file to avoid overlong command lines.
 # We ignore the exit status of the last two commands because NATIVE_SO is not
 # an essential part of the Mercury standard library for the Java
 # implementation.  Users should be able to run programs in grade Java without
 # any architecture-specific objects.
 .PHONY:	jars
 jars:	classes
-	$(JAR) $(JAR_CREATE_FLAGS) $(STD_LIB_NAME).jar mercury/*.class \
-		mercury/bit_buffer_/*.class \
-		mercury/stream_/*.class \
-		mercury/string_/*.class \
-		mercury/thread_/*.class
+	echo mercury/*.class > $(STD_LIB_NAME).classes
+	echo mercury/bit_buffer_/*.class >> $(STD_LIB_NAME).classes
+	echo mercury/stream_/*.class >> $(STD_LIB_NAME).classes
+	echo mercury/string_/*.class >> $(STD_LIB_NAME).classes
+	echo mercury/thread_/*.class >> $(STD_LIB_NAME).classes
+	$(JAR) $(JAR_CREATE_FLAGS) $(STD_LIB_NAME).jar @$(STD_LIB_NAME).classes
+	$(JAR) i $(STD_LIB_NAME).jar
+	$(RM) $(STD_LIB_NAME).classes
 	$(JAR) $(JAR_CREATE_FLAGS) $(RT_LIB_NAME).jar mercury/runtime/*.class
+	$(JAR) i $(RT_LIB_NAME).jar
 	-+cd mercury/runtime && mmake $(NATIVE_SO)
 	-cp mercury/runtime/$(NATIVE_SO) .
 
diff --git a/scripts/prepare_install_dir.in b/scripts/prepare_install_dir.in
index 38ff4a761..493a1866a 100644
--- a/scripts/prepare_install_dir.in
+++ b/scripts/prepare_install_dir.in
@@ -96,4 +96,7 @@ cp ssdb/Mercury.* ${installdir}/ssdb
 cp ssdb/.mgnuc* ${installdir}/ssdb
 cp ssdb/*FLAGS* ${installdir}/ssdb
 cp ssdb/*.m ${installdir}/ssdb
+mkdir ${installdir}/java
+mkdir ${installdir}/java/runtime
+cp java/runtime/*.java ${installdir}/java/runtime
 exit 0