diff --git a/src/kits/mail/Jamfile b/src/kits/mail/Jamfile
index ef41c300e0..eda56c234f 100644
--- a/src/kits/mail/Jamfile
+++ b/src/kits/mail/Jamfile
@@ -39,6 +39,7 @@ SharedLibrary libmail.so :
 	NodeMessage.cpp
 	numailkit.cpp
 	ProtocolConfigView.cpp
+	regex.c
 	RemoteStorageProtocol.cpp
 	StatusWindow.cpp
 	StringList.cpp