--- ./config/config.mk.orig
+++ ./config/config.mk
@@ -368,7 +368,7 @@
 else
 XPIDL_COMPILE 	= $(CYGWIN_WRAPPER) $(LIBXUL_DIST)/bin/xpidl$(BIN_SUFFIX)
 endif
-XPIDL_LINK = $(PYTHON) $(SDK_BIN_DIR)/xpt.py link
+XPIDL_LINK = $(PYTHON) $(LIBXUL_DIST)/sdk/bin/xpt.py link
 
 INCLUDES = \
   $(LOCAL_INCLUDES) \