/// <summary>
      /// Clear the internal state of the <see cref="Configuration"/> object.
      /// </summary>
      protected void Reset()
      {
         classes = new Dictionary<string, PersistentClass>(); //new SequencedHashMap(); - to make NH-369 bug deterministic
         imports = new Dictionary<string, string>();
         collections = new Dictionary<string, NHibernate.Mapping.Collection>();
         tables = new Dictionary<string, Table>();
         namedQueries = new Dictionary<string, NamedQueryDefinition>();
         namedSqlQueries = new Dictionary<string, NamedSQLQueryDefinition>();
         sqlResultSetMappings = new Dictionary<string, ResultSetMappingDefinition>();
         secondPasses = new List<SecondPassCommand>();
         propertyReferences = new List<Mappings.PropertyReference>();
         filterDefinitions = new Dictionary<string, FilterDefinition>();
         interceptor = emptyInterceptor;

//In the next Line the Exception occurs
         properties = Environment.Properties;
         auxiliaryDatabaseObjects = new List<IAuxiliaryDatabaseObject>();
         sqlFunctions = new Dictionary<string, ISQLFunction>();
         mappingsQueue = new MappingsQueue();
         eventListeners = new EventListeners();
         typeDefs = new Dictionary<string, TypeDef>();
         extendsQueue = new HashedSet<ExtendsQueueEntry>();
         tableNameBinding = new Dictionary<string, Mappings.TableDescription>();
         columnNameBindingPerTable = new Dictionary<Table, Mappings.ColumnNames>();
      }

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
  <session-factory>
    <!--properties-->
    <property name="connection.provider">NHibernate.Connection.DriverConnectionProvider</property>
    <property name="dialect">NHibernate.Dialect.MsSqlCeDialect</property>
    <property name="connection.driver_class">NHibernate.Driver.SqlServerCeDriver</property>
    <property name="connection.connection_string">Data Source=Temp.sdf</property>
    <property name="show_sql">true</property>
    <property name="proxyfactory.factory_class">NHibernate.ByteCode.Castle.ProxyFactoryFactory, NHibernate.ByteCode.Castle</property>
    <!--Mappings-->
    <!--    <mapping resource="Solution.Mappings.Product.hbm.xml" assembly="Solution"/> -->
  </session-factory>
</hibernate-configuration>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace DDT.PDMS.ProjektDatenbankFunktionen
{
    public class TempTbl
    {
        public virtual Guid Id
        {
            get;
            set;
        }
        public virtual string Name
        {
            get;
            set;
        }
    }
}

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
                   assembly="DDT.PDMS"
                   namespace="DDT.PDMS.ProjektDatenbankFunktionen">
  <class name="TempTbl">
    <id name="Id">
      <generator class="guid" />
    </id>
    <property name="Name" />
  </class>
</hibernate-mapping>