title: Entity Framework 5 on .NET 4.0 - DatabaseGeneratedOption.Identity is undefined
body: <p>I need to use EF5 on .NET 4 and I've run into a reference issue when mapping my class with HasDatabaseGenerationOption.Identity which doesn't exist in the 4.0 version of the library.</p>
  
  <p>The following is failing:</p>
  
  <pre><code>this.Property(t =&gt; t.DeploymentLogId)
                .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
  </code></pre>
  
  <p>Does anyone know of a work around?</p>