Index: TODO
===================================================================
diff -u -r842271399d11707b3bff119e57a6abe89e211df2 -r433dab40ed472f0bcddf9c2afd176e3a2ff4de0b
--- TODO	(.../TODO)	(revision 842271399d11707b3bff119e57a6abe89e211df2)
+++ TODO	(.../TODO)	(revision 433dab40ed472f0bcddf9c2afd176e3a2ff4de0b)
@@ -1967,6 +1967,9 @@
 - don't leave error message when __default_superclass (or
   __default_metaclass) is not set
 
+- Fixed switching between INACTIVE_MIXIN frames to ACTIVE_MIXIN frames
+- Extended regression test
+
 TODO:
 
 - "-returns" 
Index: generic/nsf.c
===================================================================
diff -u -r842271399d11707b3bff119e57a6abe89e211df2 -r433dab40ed472f0bcddf9c2afd176e3a2ff4de0b
--- generic/nsf.c	(.../nsf.c)	(revision 842271399d11707b3bff119e57a6abe89e211df2)
+++ generic/nsf.c	(.../nsf.c)	(revision 433dab40ed472f0bcddf9c2afd176e3a2ff4de0b)
@@ -9176,7 +9176,7 @@
      */
     if (object->mixinStack) {
       if (cscPtr->frameType == NSF_CSC_TYPE_ACTIVE_MIXIN)
-        cscPtr->frameType = NSF_CSC_TYPE_INACTIVE;
+        cscPtr->frameType = NSF_CSC_TYPE_INACTIVE_MIXIN;
 
       /* otherwise move the command pointer forward */
       if (isMixinEntry) {
@@ -15335,6 +15335,7 @@
   if (object && (object->filterStack || object->mixinStack) ) {
     CallStackUseActiveFrame(interp, &ctx);
   }
+
   if (!Tcl_Interp_varFramePtr(interp)) {
     CallStackRestoreSavedFrames(interp, &ctx);
     return NsfVarErrMsg(interp, "instvar used on ", objectName(object),