diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/AbstractType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/AbstractType.java
index ebffa8203..f335fe80c 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/AbstractType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/AbstractType.java
@@ -1,6 +1,6 @@
 /*
  * Copyright 2011, Mysema Ltd
- * 
+ *
  * 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
@@ -13,15 +13,21 @@
  */
 package com.mysema.query.sql.types;
 
-
+/**
+ * Common abstract superclass for Type implementations
+ *
+ * @author tiwe
+ *
+ * @param <T>
+ */
 public abstract class AbstractType<T> implements Type<T> {
-    
+
     private final int type;
-    
+
     public AbstractType(int type) {
         this.type = type;
     }
-    
+
     @Override
     public final int[] getSQLTypes() {
         return new int[]{type};
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/CalendarType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/CalendarType.java
index aaa20a5e2..a726d5c15 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/CalendarType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/CalendarType.java
@@ -21,6 +21,8 @@ import java.sql.Types;
 import java.util.Calendar;
 
 /**
+ * CalendarType maps Calendar to Timestamp on the JDBC level
+ *
  * @author tiwe
  *
  */
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/CurrencyType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/CurrencyType.java
index ef24e1d3e..378d7f662 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/CurrencyType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/CurrencyType.java
@@ -22,13 +22,15 @@ import java.util.Currency;
 import javax.annotation.Nullable;
 
 /**
+ * CurrencyType maps Currency to String on the JDBC level
+ *
  * @author tiwe
  *
  */
 public class CurrencyType extends AbstractType<Currency> {
 
     public CurrencyType() {
-        super(Types.TIMESTAMP);
+        super(Types.VARCHAR);
     }
 
     public CurrencyType(int type) {
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/LocaleType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/LocaleType.java
index 3627234c0..3b946df86 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/LocaleType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/LocaleType.java
@@ -23,6 +23,8 @@ import java.util.regex.Pattern;
 import javax.annotation.Nullable;
 
 /**
+ * LocaleType maps Locale to String on the JDBC level
+ *
  * @author tiwe
  *
  */
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/NumericBooleanType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/NumericBooleanType.java
index a5820f2ef..75ad920a0 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/NumericBooleanType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/NumericBooleanType.java
@@ -21,6 +21,8 @@ import java.sql.Types;
 import javax.annotation.Nullable;
 
 /**
+ * NumericBooleanType maps Boolean to 1/0 (Integer) on the JDBC level
+ *
  * @author tiwe
  *
  */
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/TrueFalseType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/TrueFalseType.java
index 9f8f19925..d70e66e20 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/TrueFalseType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/TrueFalseType.java
@@ -21,6 +21,8 @@ import java.sql.Types;
 import javax.annotation.Nullable;
 
 /**
+ * TrueFalseType maps Boolean to 'T'/'F' on the JDBC level
+ *
  * @author tiwe
  *
  */
diff --git a/querydsl-sql/src/main/java/com/mysema/query/sql/types/YesNoType.java b/querydsl-sql/src/main/java/com/mysema/query/sql/types/YesNoType.java
index a3cd0b6e3..c0c1c52f7 100644
--- a/querydsl-sql/src/main/java/com/mysema/query/sql/types/YesNoType.java
+++ b/querydsl-sql/src/main/java/com/mysema/query/sql/types/YesNoType.java
@@ -21,6 +21,8 @@ import java.sql.Types;
 import javax.annotation.Nullable;
 
 /**
+ * YesNoType maps Boolean to 'Y'/'N' on the JDBC level
+ *
  * @author tiwe
  *
  */