Fixed.

NikGovorov · NikGovorov · commit b3124d79b971 · 2011-09-03T18:21:47.000+04:00
diff --git a/src/NHibernate/Persister/Collection/OneToManyPersister.cs b/src/NHibernate/Persister/Collection/OneToManyPersister.cs
@@ -388,7 +388,7 @@ protected override ICollectionInitializer CreateSubselectInitializer(
 
 		public override object GetElementByIndex(object key, object index, ISessionImplementor session, object owner)
 		{
-			return new CollectionElementLoader(this, Factory, session.EnabledFilters).LoadElement(session, key, IncrementIndexByBase(index));
+			return new CollectionElementLoader(this, Factory, session.EnabledFilters).LoadElement(session, key, IncrementIndexByBase(index)) ?? NotFoundObject;
 		}
 		#region NH Specific
 		protected override SqlCommandInfo GenerateIdentityInsertRowString()

Original file line number	Diff line number	Diff line change
`@@ -388,7 +388,7 @@ protected override ICollectionInitializer CreateSubselectInitializer(`
`388`	`388`
`389`	`389`	`public override object GetElementByIndex(object key, object index, ISessionImplementor session, object owner)`
`390`	`390`	`{`
`391`		`- return new CollectionElementLoader(this, Factory, session.EnabledFilters).LoadElement(session, key, IncrementIndexByBase(index));`
	`391`	`+ return new CollectionElementLoader(this, Factory, session.EnabledFilters).LoadElement(session, key, IncrementIndexByBase(index)) ?? NotFoundObject;`
`392`	`392`	`}`
`393`	`393`	`#region NH Specific`
`394`	`394`	`protected override SqlCommandInfo GenerateIdentityInsertRowString()`