diff --git a/mozilla/embedding/browser/webBrowser/Makefile.in b/mozilla/embedding/browser/webBrowser/Makefile.in
index 8befa1c3b7d..76dfe298e33 100644
--- a/mozilla/embedding/browser/webBrowser/Makefile.in
+++ b/mozilla/embedding/browser/webBrowser/Makefile.in
@@ -37,6 +37,7 @@ XPIDLSRCS	= \
 		$(NULL)
 
 CPPSRCS		= \
+		nsDocShellTreeOwner.cpp		\
 		nsWebBrowser.cpp		\
 		$(NULL)
 
diff --git a/mozilla/embedding/browser/webBrowser/makefile.win b/mozilla/embedding/browser/webBrowser/makefile.win
index 6856057f9d4..e947ed997ca 100644
--- a/mozilla/embedding/browser/webBrowser/makefile.win
+++ b/mozilla/embedding/browser/webBrowser/makefile.win
@@ -33,6 +33,7 @@ XPIDLSRCS=						\
 LIBRARY_NAME=nsWebBrowser_s
 
 CPP_OBJS=											\
+		.\$(OBJDIR)\nsDocShellTreeOwner.obj			\
 		.\$(OBJDIR)\nsWebBrowser.obj			\
 		$(NULL)