diff --git a/include/trick/swig/swig_class_typedef.i b/include/trick/swig/swig_class_typedef.i
index de549175..07a15165 100644
--- a/include/trick/swig/swig_class_typedef.i
+++ b/include/trick/swig/swig_class_typedef.i
@@ -51,7 +51,15 @@
     // TYPE *
     void * temp_ptr ;
 
-    if ( SWIG_IsOK(SWIG_ConvertPtr($input, &temp_ptr,$1_descriptor, SWIG_POINTER_DISOWN)) ) {
+    SwigPyObject *sobj = SWIG_Python_GetSwigThis($input) ;
+    // isDisown is set to SWIG_POINTER_DISOWN by default
+    int isDisown = SWIG_POINTER_DISOWN ;
+    if (sobj) {
+        // isDisown is re-set based on whether the Python processor owns the input object 
+        isDisown = !sobj->own ;
+    }
+    
+    if ( SWIG_IsOK(SWIG_ConvertPtr($input, &temp_ptr,$1_descriptor, isDisown)) ) {
         $1 = reinterpret_cast< $1_ltype >(temp_ptr) ;
     } else if ( SWIG_IsOK(SWIG_ConvertPtr($input, &temp_ptr,SWIG_TypeQuery("_p_swig_ref"), 0)) ) {
         // Array to pointer assignment
diff --git a/test/SIM_test_ip/RUN_test/unit_test.py b/test/SIM_test_ip/RUN_test/unit_test.py
index 35ecab8d..746fdbe3 100644
--- a/test/SIM_test_ip/RUN_test/unit_test.py
+++ b/test/SIM_test_ip/RUN_test/unit_test.py
@@ -2781,12 +2781,16 @@ def main():
     # Polymorphic assignments and access
     test_suite = "polymorphism"
 
-    test_so.a = trick.Cat()
+    #test_so.a = trick.Cat()
+    # use MM to allocate memory for a pointer declared in S_define 
+    test_so.a = trick.TMM_declare_var_s("Cat")
     TRICK_EXPECT_EQ( test_so.a.id , 1, test_suite , "single abstract ptr" )
     trick.trick_test_add_parent( test_suite , "single abstract ptr" , "1770735610")
     #test_so.a.speak()
     #test_so.a[0].speak()
-    test_so.a = trick.Dog()
+    #test_so.a = trick.Dog()
+    # use MM to allocate memory for a pointer declared in S_define 
+    test_so.a = trick.TMM_declare_var_s("Dog")
     TRICK_EXPECT_EQ( test_so.a.id , 2, test_suite , "single abstract ptr" )
 
     test_so.aarray[0] = trick.Cat()