Index: generic/tkCanvas.c
==================================================================
--- generic/tkCanvas.c
+++ generic/tkCanvas.c
@@ -1679,15 +1679,10 @@
 	if (objc == 3) {
 	    itemPtr = NULL;
 	} else {
 	    FIRST_CANVAS_ITEM_MATCHING(objv[3], &searchPtr, goto done);
 	    if (itemPtr == NULL) {
-		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
-			"tagOrId \"%s\" doesn't match any items",
-			Tcl_GetString(objv[3])));
-		Tcl_SetErrorCode(interp, "TK", "CANVAS", "ITEM", NULL);
-		result = TCL_ERROR;
 		goto done;
 	    }
 	    itemPtr = itemPtr->prevPtr;
 	}
 	RELINK_ITEMS(objv[2], itemPtr);
@@ -1806,15 +1801,10 @@
 	    prevPtr = NULL;
 	    FOR_EVERY_CANVAS_ITEM_MATCHING(objv[3], &searchPtr, goto done) {
 		prevPtr = itemPtr;
 	    }
 	    if (prevPtr == NULL) {
-		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
-			"tagOrId \"%s\" doesn't match any items",
-			Tcl_GetString(objv[3])));
-		Tcl_SetErrorCode(interp, "TK", "CANVAS", "ITEM", NULL);
-		result = TCL_ERROR;
 		goto done;
 	    }
 	}
 	RELINK_ITEMS(objv[2], prevPtr);
 	break;

Index: tests/canvas.test
==================================================================
--- tests/canvas.test
+++ tests/canvas.test
@@ -225,10 +225,20 @@
     set x [list [.c xview]]
     .c xview scroll 2 units
     update
     lappend x [.c xview]
 } -result {{0.6 0.9} {0.66 0.96}}
+test canvas-2.5 {CanvasWidgetCmd, raise/lower option, no error on non-existing tags} -setup {
+    .c create line 0 0 10 10 -tags aline
+} -body {
+    .c raise aline noline
+    .c raise bline aline
+    .c lower aline noline
+    .c lower bline aline
+} -cleanup {
+    .c delete aline
+} -result {}
 catch {destroy .c}
 
 # Canvas used in 3.* test cases
 canvas .c -width 60 -height 40 -scrollregion {0 0 200 80} \
 	-borderwidth 0 -highlightthickness 0