diff --git a/xtrn/sbl/GNUmakefile b/xtrn/sbl/GNUmakefile
index 6d940c137905d5a8044f1541c30cec867696893f..869529005a3f977d7e70a65dc24317b61b666e03 100644
--- a/xtrn/sbl/GNUmakefile
+++ b/xtrn/sbl/GNUmakefile
@@ -18,7 +18,7 @@ ifndef XPDEV
  XPDEV		=	../../src/xpdev
 endif
 ifndef SBBS_SRC
- SBBS_SRC	:=	$(XPDEV)../sbbs3
+ SBBS_SRC	:=	$(XPDEV)/../sbbs3
 endif
 NEED_THREADS	:=	1
 include $(XPDEV)/Common.gmake