diff --git a/colourgo/vbl.s b/colourgo/vbl.s
index f31af66..f84e256 100644
--- a/colourgo/vbl.s
+++ b/colourgo/vbl.s
@@ -9,8 +9,7 @@
 
 
     .export _vblWait, _vblWaitNon2c, _vblWait2c, _vblInit2gs
-    .export _gVblWait
-    .interruptor _vblIRQCallback
+    .export _gVblWait, _vblIRQCallback
 
 
     .include "apple2.inc"