diff --git a/lib/clone.js b/lib/clone.js
index 1b0f8bf..2c18fa3 100644
--- a/lib/clone.js
+++ b/lib/clone.js
@@ -14,6 +14,10 @@ function clone(x) {
 		return x;
 	}
 
+	if (x instanceof String || x instanceof Number || x instanceof Boolean) {
+		return x.valueOf();
+	}
+
 	if(Array.isArray(x)) {
 		return cloneArray(x);
 	}
diff --git a/test/jsonPatch-test.js b/test/jsonPatch-test.js
index d4f798b..b0981e9 100644
--- a/test/jsonPatch-test.js
+++ b/test/jsonPatch-test.js
@@ -21,6 +21,24 @@ buster.testCase('jsonPatch', {
 			assert.equals(result.value, 1);
 		},
 
+		'should replace String': function() {
+			var a = { value: 0 };
+			var result = jsonPatch.apply([{ op: 'add', path: '/value', value: new String("value") }], a);
+			assert.equals(result.value, "value");
+		},
+
+		'should replace Number': function() {
+			var a = { value: 0 };
+			var result = jsonPatch.apply([{ op: 'add', path: '/value', value: new Number(1) }], a);
+			assert.equals(result.value, 1);
+		},
+
+		'should replace Boolean': function() {
+			var a = { value: 0 };
+			var result = jsonPatch.apply([{ op: 'add', path: '/value', value: new Boolean(true) }], a);
+			assert.equals(result.value, true);
+		},
+
 		'should throw': {
 			'when path is invalid': function() {
 				assert.exception(function() {