diff --git a/compiler/frontend/src/org/jetbrains/jet/resolve/DescriptorRenderer.java b/compiler/frontend/src/org/jetbrains/jet/resolve/DescriptorRenderer.java
index 4408ebf311d..aef7c264b8c 100644
--- a/compiler/frontend/src/org/jetbrains/jet/resolve/DescriptorRenderer.java
+++ b/compiler/frontend/src/org/jetbrains/jet/resolve/DescriptorRenderer.java
@@ -387,7 +387,9 @@ public class DescriptorRenderer implements Renderer<DeclarationDescriptor> {
         }
 
         public void renderClassDescriptor(ClassDescriptor descriptor, StringBuilder builder, String keyword) {
-            renderModality(descriptor.getModality(), builder);
+            if (descriptor.getKind() != ClassKind.TRAIT) {
+                renderModality(descriptor.getModality(), builder);
+            }
             builder.append(renderKeyword(keyword)).append(" ");
             renderName(descriptor, builder);
             renderTypeParameters(descriptor.getTypeConstructor().getParameters(), builder);