The following bug has been logged online:

Bug reference: 2761
Logged by: Freddy Melo Acosta
Email address: f_Melo_Acosta (AT) hotmail (DOT) com
PostgreSQL version: 8.1
Operating system: WINDOWS XP
Description: Using NHibernate witn VS .NET 2.O
Details:

Imposible establish connection with database. Hibernate responds nor
connection, In the session a null hibvernate exception. Driver from foubdry
don't work!

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