diff --git a/src/NHibernate/Cfg/Configuration.cs b/src/NHibernate/Cfg/Configuration.cs
index 06d1a168ee4..1c0db70fb95 100644
--- a/src/NHibernate/Cfg/Configuration.cs
+++ b/src/NHibernate/Cfg/Configuration.cs
@@ -2317,7 +2317,7 @@ private static T[] AppendListeners<T>(T[] existing, T[] listenersToAdd)
 		/// Generate DDL for altering tables
 		///</summary>
 		/// <seealso cref="NHibernate.Tool.hbm2ddl.SchemaUpdate"/>
-		public string[] GenerateSchemaUpdateScript(Dialect.Dialect dialect, DatabaseMetadata databaseMetadata)
+		public string[] GenerateSchemaUpdateScript(Dialect.Dialect dialect, IDatabaseMetadata databaseMetadata)
 		{
 			SecondPassCompile();
 
@@ -2397,7 +2397,7 @@ public string[] GenerateSchemaUpdateScript(Dialect.Dialect dialect, DatabaseMeta
 			return script.ToArray();
 		}
 
-		public void ValidateSchema(Dialect.Dialect dialect, DatabaseMetadata databaseMetadata)
+		public void ValidateSchema(Dialect.Dialect dialect, IDatabaseMetadata databaseMetadata)
 		{
 			SecondPassCompile();
 
diff --git a/src/NHibernate/NHibernate.csproj b/src/NHibernate/NHibernate.csproj
index c25e725fff8..19b538de969 100644
--- a/src/NHibernate/NHibernate.csproj
+++ b/src/NHibernate/NHibernate.csproj
@@ -144,6 +144,7 @@
     <Compile Include="Connection\DriverConnectionProvider.cs" />
     <Compile Include="Connection\IConnectionProvider.cs" />
     <Compile Include="Connection\UserSuppliedConnectionProvider.cs" />
+    <Compile Include="Tool\hbm2ddl\IDatabaseMetadata.cs" />
     <Compile Include="Util\DelegateHelper.cs" />
     <Compile Include="Dialect\BitwiseFunctionOperation.cs" />
     <Compile Include="Dialect\DB2Dialect.cs" />
diff --git a/src/NHibernate/Tool/hbm2ddl/DatabaseMetadata.cs b/src/NHibernate/Tool/hbm2ddl/DatabaseMetadata.cs
index 50a96ebc27d..41328e64f31 100644
--- a/src/NHibernate/Tool/hbm2ddl/DatabaseMetadata.cs
+++ b/src/NHibernate/Tool/hbm2ddl/DatabaseMetadata.cs
@@ -10,7 +10,7 @@
 
 namespace NHibernate.Tool.hbm2ddl
 {
-	public class DatabaseMetadata
+	public class DatabaseMetadata : IDatabaseMetadata
 	{
 		private static readonly IInternalLogger log = LoggerProvider.LoggerFor(typeof (DatabaseMetadata));
 
diff --git a/src/NHibernate/Tool/hbm2ddl/IDatabaseMetadata.cs b/src/NHibernate/Tool/hbm2ddl/IDatabaseMetadata.cs
new file mode 100644
index 00000000000..1f17b2bbbaf
--- /dev/null
+++ b/src/NHibernate/Tool/hbm2ddl/IDatabaseMetadata.cs
@@ -0,0 +1,11 @@
+using NHibernate.Dialect.Schema;
+
+namespace NHibernate.Tool.hbm2ddl
+{
+    public interface IDatabaseMetadata
+    {
+        ITableMetadata GetTableMetadata(string name, string schema, string catalog, bool isQuoted);
+        bool IsSequence(object key);
+        bool IsTable(object key);
+    }
+}