diff -r e3f671b50e93 -r 189f695d0b02 vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java
--- a/vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java	Wed Jan 30 22:23:21 2013 +0100
+++ b/vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java	Thu Jan 31 15:26:09 2013 +0100
@@ -532,7 +532,7 @@
                     emit(out, "@1 = @1.sub32(@2);", smapper.getI(1), smapper.popI());
                     break;
                 case opc_lsub:
-                    emit(out, "@1 -= @2;", smapper.getL(1), smapper.popL());
+                    emit(out, "@1 = @1.sub64(@2);", smapper.getL(1), smapper.popL());
                     break;
                 case opc_fsub:
                     emit(out, "@1 -= @2;", smapper.getF(1), smapper.popF());