diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/types/DeferredType.java b/compiler/frontend/src/org/jetbrains/jet/lang/types/DeferredType.java
index f43b5a98f96..36562d8dbbb 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/types/DeferredType.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/types/DeferredType.java
@@ -96,7 +96,13 @@ public class DeferredType implements JetType {
 
     @Override
     public boolean equals(Object obj) {
-        return getActualType().equals(obj);
+        if (this == obj) return true;
+        JetType actualType = getActualType();
+        if (actualType == obj) return true;
+
+        if (!(obj instanceof JetType)) return false;
+
+        return TypeUtils.equalTypes(actualType, (JetType) obj);
     }
 
     @Override
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/types/JetTypeImpl.java b/compiler/frontend/src/org/jetbrains/jet/lang/types/JetTypeImpl.java
index e711d3328bf..3670a6424d7 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/types/JetTypeImpl.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/types/JetTypeImpl.java
@@ -102,11 +102,11 @@ public final class JetTypeImpl extends AnnotatedImpl implements JetType {
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
+        if (!(o instanceof JetType)) return false;
 
-        JetTypeImpl type = (JetTypeImpl) o;
+        JetType type = (JetType) o;
 
-        return nullable == type.nullable && JetTypeChecker.INSTANCE.equalTypes(this, type);
+        return nullable == type.isNullable() && JetTypeChecker.INSTANCE.equalTypes(this, type);
     }
 
     @Override