diff -ur lcm-1.2.1/lcm-java/Makefile.in lcm-1.2.1.fixed/lcm-java/Makefile.in
--- lcm-1.2.1/lcm-java/Makefile.in	2015-01-21 22:04:22.000000000 +1000
+++ lcm-1.2.1.fixed/lcm-java/Makefile.in	2015-06-22 15:28:20.270758079 +1000
@@ -1059,6 +1059,8 @@
 	rm -f $(JARFILE)
 	$(JAR) cf $(JARFILE) -C $(JAVAROOT) .
 
+.NOTPARALLEL: # multiple jar xf invocations in parallel will race with each other
+
 $(jide_extract): $(jide_jar)
 	cd $(JAVAROOT) && $(JAR) xf ../$(jide_jar)