diff --git a/b2/Makefile b/b2/Makefile
index 2740777..4323712 100644
--- a/b2/Makefile
+++ b/b2/Makefile
@@ -97,7 +97,7 @@ try:
 # ----- Tests -----------------------------------------------------------------
 
 test tests:	all
-		LANG= sh -c \
+		LANG= bash -c \
 		  'passed=0 && cd test && \
 		  for n in [a-z]*; do \
 		  [ $$n != core ] && SCRIPT=$$n . ./$$n; done; \