diff --git a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JvmClassName.java b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JvmClassName.java
index a91357ad061..4f54eff8e42 100644
--- a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JvmClassName.java
+++ b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JvmClassName.java
@@ -38,8 +38,7 @@ public class JvmClassName {
     @NotNull
     public static JvmClassName byType(@NotNull Type type) {
         if (type.getSort() != Type.OBJECT) {
-            throw new IllegalArgumentException(
-                    "must be an object to be converted to " + JvmClassName.class.getSimpleName());
+            throw new IllegalArgumentException("Type is not convertible to " + JvmClassName.class.getSimpleName() + ": " + type);
         }
         return byInternalName(type.getInternalName());
     }