diff --git a/mailnews/mime/public/Makefile.in b/mailnews/mime/public/Makefile.in
index a7d785dc2ce0..656a22c7f030 100644
--- a/mailnews/mime/public/Makefile.in
+++ b/mailnews/mime/public/Makefile.in
@@ -25,6 +25,7 @@ include $(DEPTH)/config/autoconf.mk
 EXPORTS = \
 		nsIStreamConverter.h \
 		nsRFC822toHTMLStreamConverter.h \
+		nsIMimeHeaderConverter.h \
 		$(NULL)
 
 include $(topsrcdir)/config/config.mk
diff --git a/mailnews/mime/public/makefile.win b/mailnews/mime/public/makefile.win
index 808ada773209..064a793a3942 100644
--- a/mailnews/mime/public/makefile.win
+++ b/mailnews/mime/public/makefile.win
@@ -21,6 +21,7 @@ IGNORE_MANIFEST=1
 EXPORTS =					\
 	nsIStreamConverter.h			\
 	nsIMimeObjectClassAccess.h		\
+	nsIMimeHeaderConverter.h		\
         $(NULL)
 
 MODULE=mime