diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
index 007ddd3579e..ff8c4f20915 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
@@ -3043,9 +3043,8 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
                 JetExpression left = binaryExpression.getLeft();
                 JetExpression right = binaryExpression.getRight();
                 Type leftType = expressionType(left);
-                Type rightType = expressionType(right);
 
-                if (leftType.equals(JAVA_STRING_TYPE) && rightType.equals(JAVA_STRING_TYPE)) {
+                if (leftType.equals(JAVA_STRING_TYPE)) {
                     invokeAppend(left);
                     invokeAppend(right);
                     return;
diff --git a/compiler/testData/codegen/box/strings/stringBuilderAppend.kt b/compiler/testData/codegen/box/strings/stringBuilderAppend.kt
new file mode 100644
index 00000000000..b370acf3954
--- /dev/null
+++ b/compiler/testData/codegen/box/strings/stringBuilderAppend.kt
@@ -0,0 +1,16 @@
+class A() {
+
+    override fun toString(): String {
+        return "A"
+    }
+}
+
+fun box() : String {
+
+    val s = "1" + "2" + 3 + 4L + 5.0 + 6F + '7' + A()
+
+    if (s != "12345.06.07A") return "fail $s"
+
+    return "OK"
+}
+
diff --git a/compiler/testData/codegen/bytecodeText/stringBuilderAppend.kt b/compiler/testData/codegen/bytecodeText/stringBuilderAppend.kt
new file mode 100644
index 00000000000..70b73e9a879
--- /dev/null
+++ b/compiler/testData/codegen/bytecodeText/stringBuilderAppend.kt
@@ -0,0 +1,16 @@
+class A() {
+
+    override fun toString(): String {
+        return "A"
+    }
+}
+
+
+fun box() : String {
+
+    val s = "1" + "2" + 3 + 4L + 5.0 + 6F + '7' + A()
+
+    return s
+}
+
+// 1 NEW java/lang/StringBuilder
\ No newline at end of file
diff --git a/compiler/tests/org/jetbrains/jet/codegen/BytecodeTextTestGenerated.java b/compiler/tests/org/jetbrains/jet/codegen/BytecodeTextTestGenerated.java
index 55e9436aac8..3084484a0b9 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/BytecodeTextTestGenerated.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/BytecodeTextTestGenerated.java
@@ -177,6 +177,12 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
         doTest(fileName);
     }
     
+    @TestMetadata("stringBuilderAppend.kt")
+    public void testStringBuilderAppend() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/stringBuilderAppend.kt");
+        doTest(fileName);
+    }
+    
     @TestMetadata("topLevelFunWithDefaultArgs.kt")
     public void testTopLevelFunWithDefaultArgs() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/topLevelFunWithDefaultArgs.kt");
diff --git a/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java b/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
index 5657c063c42..97dfe9eae63 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
@@ -5990,6 +5990,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             doTest(fileName);
         }
         
+        @TestMetadata("stringBuilderAppend.kt")
+        public void testStringBuilderAppend() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/box/strings/stringBuilderAppend.kt");
+            doTest(fileName);
+        }
+        
     }
     
     @TestMetadata("compiler/testData/codegen/box/super")