diff --git a/main/Makefile b/main/Makefile
index e476969c9a..e0b7135a10 100644
--- a/main/Makefile
+++ b/main/Makefile
@@ -253,6 +253,7 @@ ifeq ($(PJPROJECT_BUNDLED),yes)
 ASTPJ_SO_VERSION=2
 ASTPJ_LDLIBS=-L. -lasteriskpj
 
+PJDIR=$(ASTTOPDIR)/$(PJPROJECT_DIR)/source
 -include $(ASTTOPDIR)/$(PJPROJECT_DIR)/build.mak
 
 PJPROJECT_LDLIBS := \