Index: trunk/src/extobj.h
===================================================================
--- trunk/src/extobj.h	(revision 28734)
+++ trunk/src/extobj.h	(revision 28735)
@@ -29,6 +29,8 @@
 
 #include <genvector/vtp0.h>
 
+#include "board.h"
+#include "data.h"
 #include "obj_common.h"
 #include "obj_subc.h"
 #include "draw.h"
@@ -133,5 +135,39 @@
 		eo->edit_geo(sc, edit_obj);
 }
 
+PCB_INLINE void pcb_extobj_new_subc(pcb_any_obj_t *edit_obj, pcb_subc_t *subc_copy_attr_from)
+{
+	pcb_data_t *data;
+	pcb_board_t *pcb;
+	pcb_subc_t *sc;
+	char tmp[128];
 
+	if (edit_obj->parent_type == PCB_PARENT_DATA)
+		data = edit_obj->parent.data;
+	else if (edit_obj->parent_type == PCB_PARENT_LAYER)
+		data = edit_obj->parent.layer->parent.data;
+	else
+		return;
+
+	pcb = pcb_data_get_top(data);
+	if (pcb == NULL)
+		return;
+	
+	sc = pcb_subc_new();
+	sc->ID = pcb_create_ID_get();
+	pcb_subc_reg(pcb->Data, sc);
+	pcb_obj_id_reg(pcb->Data, sc);
+
+	if (subc_copy_attr_from != NULL)
+		pcb_attribute_copy_all(&sc->Attributes, &subc_copy_attr_from->Attributes);
+
+	sprintf(tmp, "%ld", sc->ID);
+	pcb_attribute_put(&edit_obj->Attributes, "extobj::subcobj", tmp);
+	sprintf(tmp, "%ld", edit_obj->ID);
+	pcb_attribute_put(&sc->Attributes, "extobj::editobj", tmp);
+
+	pcb_extobj_edit_pre(edit_obj);
+	pcb_extobj_edit_geo(edit_obj);
+}
+
 #endif
Index: trunk/src/obj_common.c
===================================================================
--- trunk/src/obj_common.c	(revision 28734)
+++ trunk/src/obj_common.c	(revision 28735)
@@ -39,6 +39,7 @@
 #include "obj_subc.h"
 #include "obj_subc_parent.h"
 #include "obj_term.h"
+#include "extobj.h"
 
 const char *pcb_obj_type_name(pcb_objtype_t type)
 {
@@ -124,12 +125,58 @@
 	return ID++;
 }
 
+static void pcb_attribute_copy_all_smart(pcb_attribute_list_t *dest, const pcb_attribute_list_t *src, pcb_any_obj_t *dstobj)
+{
+	int i, exto = 0;
+	const char *subcobj;
+
+	for (i = 0; i < src->Number; i++) {
+		if (strncmp(src->List[i].name, "extobj", 6) == 0) {
+			exto = 1;
+			if (strcmp(src->List[i].name+6, "::subcobj") == 0) {
+				subcobj = src->List[i].value;
+				continue; /* do not copy, will be re-generated */
+			}
+		}
+
+		pcb_attribute_put(dest, src->List[i].name, src->List[i].value);
+	}
+	if (exto) {
+		pcb_subc_t *copy_from = NULL;
+		if (subcobj != NULL) {
+			pcb_data_t *data;
+
+			if (dstobj->parent_type == PCB_PARENT_DATA)
+				data = dstobj->parent.data;
+			else if (dstobj->parent_type == PCB_PARENT_LAYER)
+				data = dstobj->parent.layer->parent.data;
+			else
+				data = NULL;
+
+			if (data != NULL) {
+				char *end;
+				long id = strtol(subcobj, &end, 10);
+				if (*end == '\0') {
+					copy_from = htip_get(&data->id2obj, id);
+					if ((copy_from != NULL) && (copy_from->type != PCB_OBJ_SUBC))
+						copy_from = NULL;
+				}
+			}
+		}
+		pcb_extobj_new_subc(dstobj, copy_from);
+	}
+}
+
+
 void pcb_obj_add_attribs(void *obj, const pcb_attribute_list_t *src, pcb_bool smart)
 {
 	pcb_any_obj_t *o = obj;
 	if (src == NULL)
 		return;
-	pcb_attribute_copy_all(&o->Attributes, src);
+	if (smart)
+		pcb_attribute_copy_all_smart(&o->Attributes, src, obj);
+	else
+		pcb_attribute_copy_all(&o->Attributes, src);
 }
 
 void pcb_obj_center(const pcb_any_obj_t *obj, pcb_coord_t *x, pcb_coord_t *y)