Index: TODO
===================================================================
diff -u -r6c5a4270b7d010efabb4cb89a890006b059a5f7e -r4c9e3b2b545a49698aa2284cc8dc5d5bb2719703
--- TODO	(.../TODO)	(revision 6c5a4270b7d010efabb4cb89a890006b059a5f7e)
+++ TODO	(.../TODO)	(revision 4c9e3b2b545a49698aa2284cc8dc5d5bb2719703)
@@ -4208,12 +4208,15 @@
 XOTcl 2
 - don't blindly register all object/class methods for XOTcl
 
+nsf.c: 
+- fix potential bad interaction between per-object mixins and
+  per-class caching of object-parameters
+
 ========================================================================
 TODO:
 - regression tests for "/obj/ info lookup parameter ...."
-- check potential mis-cachings due to per-object/per-class mixins,
-  when object-parameters are e.g. manually invalidated.
-- do we need NSF_CONFIGURE, NSF_INITIALIZE, NSF_ASSIGN
+- handling of "required" in reconfigure (see 
+  parameter-object-mixin-dependency in parameters.test)
 - check noconfig
 - "/obj/ configure" returns values which can't be read via "/obj/ cget"
   (but altered properly via "configure").
Index: generic/nsf.c
===================================================================
diff -u -r5d1617640ad71fd52b069f81cfcadbe4cbb6f2a2 -r4c9e3b2b545a49698aa2284cc8dc5d5bb2719703
--- generic/nsf.c	(.../nsf.c)	(revision 5d1617640ad71fd52b069f81cfcadbe4cbb6f2a2)
+++ generic/nsf.c	(.../nsf.c)	(revision 4c9e3b2b545a49698aa2284cc8dc5d5bb2719703)
@@ -21583,9 +21583,13 @@
   NsfClass *class;
 
   assert(object);
-  if (object->flags & NSF_HAS_PER_OBJECT_SLOTS) {
-    assert(object->flags & NSF_INIT_CALLED);
-    assert(object->nsPtr != NULL);
+  if ((object->flags & NSF_HAS_PER_OBJECT_SLOTS)
+      || (object->opt && object->opt->objMixins)
+      ) {
+    /* 
+     * We have object-specific parameters.  Do not use the per-class cache,
+     * and do not save the results in the per-class cache
+     */
     /*fprintf(stderr, "per-object configure obj %s flags %.6x\n", 
       ObjectName(object), object->flags);*/
     class = NULL;
Index: tests/parameters.test
===================================================================
diff -u -r5d1617640ad71fd52b069f81cfcadbe4cbb6f2a2 -r4c9e3b2b545a49698aa2284cc8dc5d5bb2719703
--- tests/parameters.test	(.../parameters.test)	(revision 5d1617640ad71fd52b069f81cfcadbe4cbb6f2a2)
+++ tests/parameters.test	(.../parameters.test)	(revision 4c9e3b2b545a49698aa2284cc8dc5d5bb2719703)
@@ -1831,19 +1831,73 @@
 }
 
 #
-# Test incfluence of mixins on objectparameters
+# Test interactions between per-object-mixins and objectparameters 
+# (case without per-object property)
 #
 nx::Test case parameter-object-mixin-dependency {
   nx::Class create C {
     :property a1
+    :create c1
+  }
+  nx::Class create D -superclass C
+  nx::Class create M {:property b1:required}
+
+  ? {c1 eval :__objectparameter} "-a1 -volatile:alias,noarg -properties:alias,method=::nx::internal::addProperties -noinit:alias,method=::nsf::methods::object::noinit,noarg -mixin:mixinreg,alias,0..n -class:class,alias,method=::nsf::methods::object::class -filter:filterreg,alias,0..n __initcmd:initcmd,optional,noleadingdash"
+  
+  c1 mixin M
+
+  ? {c1 info precedence} "::M ::C ::nx::Object"
+
+  ? {c1 eval :__objectparameter} "-b1:required -a1 -volatile:alias,noarg -properties:alias,method=::nx::internal::addProperties -noinit:alias,method=::nsf::methods::object::noinit,noarg -mixin:mixinreg,alias,0..n -class:class,alias,method=::nsf::methods::object::class -filter:filterreg,alias,0..n __initcmd:initcmd,optional,noleadingdash"
+
+  #
+  # Invalidate the object parameter and expect that the per-class
+  # mixin does not harm
+  #
+  ::nsf::invalidateobjectparameter C
+
+  # 
+  # We have now "-b1:required" in the object parameters.  
+  #
+  # TODO: Actually we should enforce it. We could check, if the
+  # associate variable is already set, but this does not work for
+  # aliases.... we could track, if the slot is already initialized for
+  # this object. This can be a potentially huge table containing
+  # potentially all objects (relation slots). Maybe keep the table
+  # just for "required" parameters? or look for an approach based on
+  # epoch counting?
+  #
+  ? {c1 configure -a1 x} ""
+
+  #
+  # The object parameter based on the per-object-mixin must not be
+  # stored in the class based cache. Therefore, creating a new object
+  # must not require b1
+
+  ? {C create c2} ::c2
+  
+  #
+  # the same should hold for subcles
+  #
+  ? {D create d1} ::d1
+
+
+}
+
+
+#
+# Test interactions between per-object-mixins and objectparameters 
+# (case with per-object property)
+#
+nx::Test case parameter-object-mixin-dependency-object-property {
+  nx::Class create C {
+    :property a1
     :create c1 {
       :property a2
     }
   }
-
-  nx::Class create M {
-    :property b1:required
-  }
+  nx::Class create D -superclass C
+  nx::Class create M {:property b1:required}
   
   c1 mixin M
 
@@ -1869,10 +1923,11 @@
 
   # should not require b1
   ? {C create c2} ::c2
- 
+
 }
 
 
+
 #
 # Test integer, wideinteger and bignums
 #