Index: libnautilus-private/nautilus-dnd.c
===================================================================
RCS file: /cvs/gnome/nautilus/libnautilus-private/nautilus-dnd.c,v
retrieving revision 1.24
diff -u -p -r1.24 nautilus-dnd.c
--- libnautilus-private/nautilus-dnd.c	18 Mar 2006 07:13:49 -0000	1.24
+++ libnautilus-private/nautilus-dnd.c	20 Apr 2006 11:19:18 -0000
@@ -302,6 +302,26 @@ nautilus_drag_default_drop_action_for_ur
 	return context->suggested_action;
 }
 
+static gboolean
+uri_is_user_owned (GnomeVFSURI *uri)
+{
+	gboolean user_owned;
+
+	user_owned = FALSE;
+
+	if (uri != NULL && !strcmp (gnome_vfs_uri_get_scheme (uri), "file")) {
+		GnomeVFSFileInfo *info;
+
+		info = gnome_vfs_file_info_new ();
+		if (gnome_vfs_get_file_info_uri (uri, info, GNOME_VFS_FILE_INFO_GET_ACCESS_RIGHTS) == GNOME_VFS_OK) {
+			user_owned = (info->valid_fields & GNOME_VFS_FILE_INFO_FIELDS_IDS) &&
+				     geteuid () == info->uid;
+		}
+		gnome_vfs_file_info_unref (info);
+	}
+
+	return user_owned;
+}
 
 void
 nautilus_drag_default_drop_action_for_icons (GdkDragContext *context,
@@ -385,11 +405,12 @@ nautilus_drag_default_drop_action_for_ic
 	if (dropped_uri != NULL) {
 		gnome_vfs_check_same_fs_uris (dropped_uri, target_uri, &same_fs);
 		target_is_source_parent = gnome_vfs_uri_is_parent (target_uri, dropped_uri, FALSE);
-		gnome_vfs_uri_unref (dropped_uri);
 	}
-	gnome_vfs_uri_unref (target_uri);
-	
-	if (same_fs || target_is_source_parent) {
+
+	if ((same_fs || target_is_source_parent) &&
+	    /* use copy by default when dragging from user-owned location
+	     * to location owned by somebody else */
+	    !(uri_is_user_owned (dropped_uri) && !uri_is_user_owned (target_uri))) {
 		if (actions & GDK_ACTION_MOVE) {
 			*action = GDK_ACTION_MOVE;
 		} else {
@@ -402,6 +423,15 @@ nautilus_drag_default_drop_action_for_ic
 			*action = context->suggested_action;
 		}
 	}
+
+	if (dropped_uri != NULL) {
+		gnome_vfs_uri_unref (dropped_uri);
+	}
+
+	if (target_uri != NULL) {
+		gnome_vfs_uri_unref (target_uri);
+	}
+	
 }
 
 /* Encode a "x-special/gnome-icon-list" selection.