diff --git a/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqName.java b/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqName.java
index beda81c39a4..ac17bfdf420 100644
--- a/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqName.java
+++ b/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqName.java
@@ -17,8 +17,8 @@
 package org.jetbrains.jet.lang.resolve.name;
 
 import com.google.common.collect.Lists;
-import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.jet.utils.UtilsPackage;
 
 import java.util.List;
 
@@ -26,8 +26,7 @@ public final class FqName extends FqNameBase {
 
     @NotNull
     public static FqName fromSegments(@NotNull List<String> names) {
-        String fqName = StringUtil.join(names, ".");
-        return new FqName(fqName);
+        return new FqName(UtilsPackage.join(names, "."));
     }
 
     public static final FqName ROOT = new FqName("");
diff --git a/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqNameUnsafe.java b/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqNameUnsafe.java
index dca26fd0757..c660913e076 100644
--- a/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqNameUnsafe.java
+++ b/core/descriptors/src/org/jetbrains/jet/lang/resolve/name/FqNameUnsafe.java
@@ -17,9 +17,9 @@
 package org.jetbrains.jet.lang.resolve.name;
 
 import com.google.common.collect.Lists;
-import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.jet.utils.UtilsPackage;
 
 import java.util.List;
 
@@ -256,8 +256,7 @@ public final class FqNameUnsafe extends FqNameBase {
 
     @NotNull
     public static FqNameUnsafe fromSegments(@NotNull List<Name> names) {
-        String fqName = StringUtil.join(names, ".");
-        return new FqNameUnsafe(fqName);
+        return new FqNameUnsafe(UtilsPackage.join(names, "."));
     }
 
 
diff --git a/core/descriptors/src/org/jetbrains/jet/renderer/DescriptorRendererImpl.java b/core/descriptors/src/org/jetbrains/jet/renderer/DescriptorRendererImpl.java
index 191cf12bfe2..db32e79254f 100644
--- a/core/descriptors/src/org/jetbrains/jet/renderer/DescriptorRendererImpl.java
+++ b/core/descriptors/src/org/jetbrains/jet/renderer/DescriptorRendererImpl.java
@@ -18,7 +18,6 @@ package org.jetbrains.jet.renderer;
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
-import com.intellij.openapi.util.text.StringUtil;
 import kotlin.Function1;
 import kotlin.KotlinPackage;
 import org.jetbrains.annotations.NotNull;
@@ -39,6 +38,7 @@ import org.jetbrains.jet.lang.resolve.name.Name;
 import org.jetbrains.jet.lang.types.*;
 import org.jetbrains.jet.lang.types.error.MissingDependencyErrorClass;
 import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
+import org.jetbrains.jet.utils.UtilsPackage;
 
 import java.util.*;
 
@@ -408,7 +408,7 @@ public class DescriptorRendererImpl implements DescriptorRenderer {
         StringBuilder sb = new StringBuilder();
         sb.append(renderType(annotation.getType()));
         if (verbose) {
-            sb.append("(").append(StringUtil.join(renderAndSortAnnotationArguments(annotation), ", ")).append(")");
+            sb.append("(").append(UtilsPackage.join(renderAndSortAnnotationArguments(annotation), ", ")).append(")");
         }
         return sb.toString();
     }
@@ -436,15 +436,15 @@ public class DescriptorRendererImpl implements DescriptorRenderer {
 
                     @Override
                     public String visitArrayValue(ArrayValue value, Void data) {
-                        List<CompileTimeConstant<?>> elements = value.getValue();
-                        if (elements.isEmpty()) return "{}";
-                        List<String> renderedElements = KotlinPackage.map(elements, new Function1<CompileTimeConstant<?>, String>() {
-                            @Override
-                            public String invoke(CompileTimeConstant<?> constant) {
-                                return renderConstant(constant);
-                            }
-                        });
-                        return "{" + StringUtil.join(renderedElements, ", ") + "}";
+                        List<String> renderedElements =
+                                KotlinPackage.map(value.getValue(),
+                                                  new Function1<CompileTimeConstant<?>, String>() {
+                                                      @Override
+                                                      public String invoke(CompileTimeConstant<?> constant) {
+                                                          return renderConstant(constant);
+                                                      }
+                                                  });
+                        return "{" + UtilsPackage.join(renderedElements, ", ") + "}";
                     }
 
                     @Override
@@ -681,7 +681,7 @@ public class DescriptorRendererImpl implements DescriptorRenderer {
         }
         if (!upperBoundStrings.isEmpty()) {
             builder.append(" ").append(renderKeyword("where")).append(" ");
-            builder.append(StringUtil.join(upperBoundStrings, ", "));
+            builder.append(UtilsPackage.join(upperBoundStrings, ", "));
         }
     }
 
diff --git a/core/util.runtime/src/org/jetbrains/jet/utils/strings.kt b/core/util.runtime/src/org/jetbrains/jet/utils/strings.kt
new file mode 100644
index 00000000000..e0d24939497
--- /dev/null
+++ b/core/util.runtime/src/org/jetbrains/jet/utils/strings.kt
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.jet.utils
+
+// Needed for Java interop: otherwise you need to specify all the optional parameters to join, i.e. prefix, postfix, limit, truncated
+fun Iterable<Any>.join(separator: String) = joinToString(separator)