diff --git a/mailnews/compose/tests/compose2/Makefile.in b/mailnews/compose/tests/compose2/Makefile.in
index d548b4813b7..a682682653d 100644
--- a/mailnews/compose/tests/compose2/Makefile.in
+++ b/mailnews/compose/tests/compose2/Makefile.in
@@ -39,6 +39,11 @@ LIBS		= \
 		-lmsgbaseutil \
 		$(NULL)
 
+# The Timer libs for Photon/Neutrino require the Toolkit libs to also be linked
+#  in.
+ifeq ($(TARGET_OS),nto)
+EXTRA_LIBS         +=  		$(TK_LIBS)
+endif
 
 include $(topsrcdir)/config/rules.mk
 
diff --git a/mailnews/compose/tests/sendlater/Makefile.in b/mailnews/compose/tests/sendlater/Makefile.in
index 4d43665f4ca..e815aec7f51 100644
--- a/mailnews/compose/tests/sendlater/Makefile.in
+++ b/mailnews/compose/tests/sendlater/Makefile.in
@@ -39,5 +39,11 @@ LIBS		= \
 		$(NSPR_LIBS) \
 		$(NULL)
 
+# The Timer libs for Photon/Neutrino require the Toolkit libs to also be linked
+#  in.
+ifeq ($(TARGET_OS),nto)
+EXTRA_LIBS         +=  		$(TK_LIBS)
+endif
+
 include $(topsrcdir)/config/rules.mk