diff --git a/Classes/NVPolylineAnnotation.m b/Classes/NVPolylineAnnotation.m
index e6099cf..d936b3a 100644
--- a/Classes/NVPolylineAnnotation.m
+++ b/Classes/NVPolylineAnnotation.m
@@ -16,7 +16,7 @@ @implementation NVPolylineAnnotation
 -(id) initWithPoints:(NSArray*) points mapView:(MKMapView *)mapView {
 	self = [super init];
 	
-	_points = [[NSArray alloc] initWithArray:points];
+	_points = [points mutableCopy];
 	_mapView = [mapView retain];
 		
 	return self;