R – ActiveWriter and NHibernate: Can’t generate

I'm trying to generate NHibernate mappings with ActiveRecord. I can create classes from a diagram by targeting ActiveRecord, but whenever I target NHibernate, I get the following error:

Error 1 Running transformation: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. —> System.IO.FileNotFoundException: Could not load file or assembly 'NHibernate, Version=1.2.0.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4' or one of its dependencies. The system cannot find the file specified.
File name: 'NHibernate, Version=1.2.0.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4'
at Castle.ActiveRecord.ActiveRecordStarter.SetUpConfiguration(IConfigurationSource source, Type type, ISessionFactoryHolder holder)
at Castle.ActiveRecord.ActiveRecordStarter.Initialize(IConfigurationSource source, Type[] types)
at Castle.ActiveRecord.ActiveRecordStarter.Initialize(Assembly assembly, IConfigurationSource source)

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].

I am referencing the NHibernate DLL, but it is version 2.0.1.4000 . I added the following into the web.config:
<dependentAssembly>
<assemblyIdentity name="NHibernate" publicKeyToken="aa95f207798dfdb4" culture="neutral"/>
<bindingRedirect oldVersion="1.0.0.0-1.2.0.4000" newVersion="2.0.1.4000"/>
</dependentAssembly>

but it is still trying to grab the old NHibernate DLL. Is there something else that must be done to use the new NHibernate?