diff --git a/Cantera/src/thermo/.cvsignore b/Cantera/src/thermo/.cvsignore
index 2f90591ed..adadf2453 100644
--- a/Cantera/src/thermo/.cvsignore
+++ b/Cantera/src/thermo/.cvsignore
@@ -1,3 +1,4 @@
 *.d
 .depends
 Makefile
+SunWS_cache
diff --git a/Cantera/src/thermo/Makefile.in b/Cantera/src/thermo/Makefile.in
index 12f9237a1..bea93ec37 100644
--- a/Cantera/src/thermo/Makefile.in
+++ b/Cantera/src/thermo/Makefile.in
@@ -58,6 +58,9 @@ clean:
             echo "$(RM) $(LIB)" ; \
           fi)
 	$(RM) *.o *~  .depends
+	(if test -d SunWS_cache ; then \
+           $(RM) -rf SunWS_cache ; \
+         fi )
 
 depends: $(DEPENDS)
 	cat *.d > .depends
diff --git a/Cantera/src/zeroD/.cvsignore b/Cantera/src/zeroD/.cvsignore
index 57751bad9..908ff2699 100644
--- a/Cantera/src/zeroD/.cvsignore
+++ b/Cantera/src/zeroD/.cvsignore
@@ -1,2 +1,3 @@
 Makefile
+SunWS_cache
 .depends
diff --git a/Cantera/src/zeroD/Makefile.in b/Cantera/src/zeroD/Makefile.in
index 400b85cf4..d7be4a4e4 100644
--- a/Cantera/src/zeroD/Makefile.in
+++ b/Cantera/src/zeroD/Makefile.in
@@ -61,6 +61,9 @@ clean:
             echo "$(RM) $(ZEROD_LIB)" ; \
           fi)
 	$(RM) *.o *~ .depends
+	(if test -d SunWS_cache ; then \
+           $(RM) -rf SunWS_cache ; \
+         fi )
 
 depends: $(DEPENDS)
 	cat *.d > .depends