diff --git a/js/js.translator/src/org/jetbrains/k2js/translate/intrinsic/functions/factories/TopLevelFIF.java b/js/js.translator/src/org/jetbrains/k2js/translate/intrinsic/functions/factories/TopLevelFIF.java
index 5715631d03c..32cb2b66979 100644
--- a/js/js.translator/src/org/jetbrains/k2js/translate/intrinsic/functions/factories/TopLevelFIF.java
+++ b/js/js.translator/src/org/jetbrains/k2js/translate/intrinsic/functions/factories/TopLevelFIF.java
@@ -35,7 +35,6 @@ import org.jetbrains.jet.lang.types.JetType;
 import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
 import org.jetbrains.jet.lang.types.lang.PrimitiveType;
 import org.jetbrains.k2js.translate.context.TranslationContext;
-import org.jetbrains.k2js.translate.intrinsic.functions.basic.BuiltInFunctionIntrinsic;
 import org.jetbrains.k2js.translate.intrinsic.functions.basic.FunctionIntrinsic;
 import org.jetbrains.k2js.translate.intrinsic.functions.patterns.DescriptorPredicate;
 import org.jetbrains.k2js.translate.intrinsic.functions.patterns.NamePredicate;
@@ -119,7 +118,7 @@ public final class TopLevelFIF extends CompositeFIF {
     public static final FunctionIntrinsicFactory INSTANCE = new TopLevelFIF();
 
     private TopLevelFIF() {
-        add(pattern("jet", "toString").receiverExists(true), new BuiltInFunctionIntrinsic("toString"));
+        add(pattern("jet", "toString").receiverExists(true), new KotlinFunctionIntrinsic("toString"));
         add(pattern("jet", "equals").receiverExists(true), EQUALS);
         add(pattern(NamePredicate.PRIMITIVE_NUMBERS, "equals"), EQUALS);
         add(pattern("String|Boolean|Char|Number.equals"), EQUALS);
diff --git a/js/js.translator/testFiles/kotlin_lib.js b/js/js.translator/testFiles/kotlin_lib.js
index 2244398b899..25effe55ea0 100644
--- a/js/js.translator/testFiles/kotlin_lib.js
+++ b/js/js.translator/testFiles/kotlin_lib.js
@@ -35,16 +35,8 @@ String.prototype.contains = function (s) {
             return obj2 == null;
         }
 
-        if (obj1 instanceof Array) {
-            if (!(obj2 instanceof Array) || obj1.length != obj2.length) {
-                return false;
-            }
-            for (var i = 0; i < obj1.length; i++) {
-                if (!Kotlin.equals(obj1[i], obj2[i])) {
-                    return false;
-                }
-            }
-            return true;
+        if (Array.isArray(obj1)) {
+            return Kotlin.arrayEquals(obj1, obj2);
         }
 
         if (typeof obj1 == "object" && obj1.equals !== undefined) {
@@ -53,6 +45,22 @@ String.prototype.contains = function (s) {
 
         return obj1 === obj2;
     };
+    
+    Kotlin.toString = function (o) {
+        if (o == null) {
+            return "null";
+        }
+        else if (Array.isArray(o)) {
+            return Kotlin.arrayToString(o);
+        }
+        else {
+            return o.toString();
+        }
+    };
+    
+    Kotlin.arrayToString = function(a) {
+        return "[" + a.join(", ") + "]";
+    };
 
     Kotlin.intUpto = function (from, to) {
         return Kotlin.$new(Kotlin.NumberRange)(from, to);
@@ -298,6 +306,22 @@ String.prototype.contains = function (s) {
         return isNaN(r) ? null : r;
     };
 
+    Kotlin.arrayEquals = function (a, b) {
+        if (a === b) {
+            return true;
+        }
+        if (!Array.isArray(b) || a.length !== b.length) {
+            return false;
+        }
+
+        for (var i = 0, n = a.length; i < n; i++) {
+            if (!Kotlin.equals(a[i], b[i])) {
+                return false;
+            }
+        }
+        return true;
+    };
+
     Kotlin.System = function () {
         var output = "";
 
@@ -427,12 +451,12 @@ String.prototype.contains = function (s) {
         return Kotlin.$new(ComparatorImpl)(f);
     };
 
-    Kotlin.collectionsMax = function (col, comp) {
-        var it = col.iterator();
-        if (col.isEmpty()) {
+    Kotlin.collectionsMax = function (c, comp) {
+        if (c.isEmpty()) {
             //TODO: which exception?
-            throw Kotlin.Exception();
+            throw new Error();
         }
+        var it = c.iterator();
         var max = it.next();
         while (it.hasNext()) {
             var el = it.next();
diff --git a/js/js.translator/testFiles/kotlin_lib_ecma3.js b/js/js.translator/testFiles/kotlin_lib_ecma3.js
index 995eedf4437..82e9fc59484 100644
--- a/js/js.translator/testFiles/kotlin_lib_ecma3.js
+++ b/js/js.translator/testFiles/kotlin_lib_ecma3.js
@@ -12,6 +12,12 @@ var Kotlin = {};
     var emptyFunction = function () {
     };
 
+    if (!Array.isArray) {
+        Array.isArray = function (vArg) {
+            return Object.prototype.toString.call(vArg) === "[object Array]";
+        };
+    }
+
     if (!Function.prototype.bind) {
         Function.prototype.bind = function (oThis) {
             if (typeof this !== "function") {