With NHibernate 4.0 the support for Iesi.Collections.ISet has been dropped must now be replaced with System.Collections.Generic.ISet< T > See: https://github.com/devbridge/BetterModules/blob/67dea3ad353cce22cced644d4d7b01184db1f890/BetterModules.Core/DataAccess/DataContext/EventListeners/DeleteEventListener.cs#L42
With NHibernate 4.0 the support for Iesi.Collections.ISet has been dropped must now be replaced with System.Collections.Generic.ISet< T >
See:
BetterModules/BetterModules.Core/DataAccess/DataContext/EventListeners/DeleteEventListener.cs
Line 42 in 67dea3a