diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java b/compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java
index 2627052c652..a43b8af9573 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java
@@ -298,15 +298,6 @@ public class JetTypeMapper {
             throw new IllegalStateException("should not compile an error type");
         }
 
-        if (standardLibrary.getComparable().equals(descriptor)) {
-            if (jetType.getArguments().size() != 1) {
-                throw new UnsupportedOperationException("Comparable must have one type argument");
-            }
-
-            // todo signature
-            return JL_COMPARABLE_TYPE;
-        }
-
         if (standardLibrary.getArray().equals(descriptor)) {
             if (jetType.getArguments().size() != 1) {
                 throw new UnsupportedOperationException("arrays must have one type argument");
@@ -334,9 +325,19 @@ public class JetTypeMapper {
         }
 
         if (descriptor instanceof ClassDescriptor) {
-            
-            String name = getFQName(descriptor);
-            Type asmType = Type.getObjectType(name + (kind == OwnerKind.TRAIT_IMPL ? JvmAbi.TRAIT_IMPL_SUFFIX : ""));
+
+            Type asmType;
+
+            if (standardLibrary.getComparable().equals(descriptor)) {
+                if (jetType.getArguments().size() != 1) {
+                    throw new UnsupportedOperationException("Comparable must have one type argument");
+                }
+
+                asmType = JL_COMPARABLE_TYPE;
+            } else {
+                String name = getFQName(descriptor);
+                asmType = Type.getObjectType(name + (kind == OwnerKind.TRAIT_IMPL ? JvmAbi.TRAIT_IMPL_SUFFIX : ""));
+            }
 
             if (signatureVisitor != null) {
                 signatureVisitor.writeClassBegin(asmType.getInternalName(), jetType.isNullable());
diff --git a/compiler/testData/writeSignature/Comparable.kt b/compiler/testData/writeSignature/Comparable.kt
new file mode 100644
index 00000000000..d8d4cc44363
--- /dev/null
+++ b/compiler/testData/writeSignature/Comparable.kt
@@ -0,0 +1,6 @@
+fun cc(): Comparable<java.lang.CharSequence>? = null
+
+// method: namespace::cc
+// jvm signature:     ()Ljava/lang/Comparable;
+// generic signature: ()Ljava/lang/Comparable<Ljava/lang/CharSequence;>;
+// kotlin signature:  ()?Ljava/lang/Comparable<Ljava/lang/CharSequence;>;