João,
Its best to be on Client Access V5R2 or later (with current all PTFs) to be
fully supported from .NET. (I understand that you can remain on an older
OS/400 such as V4R5, its the client that needs to be current).
http://www-1.ibm.com/servers/eserver/iseries/access/oledb/index.html
http://www-912.ibm.com/n_dir/nas4ap...6be4003c8957?OpenDocument&Highlight=2,ii13341
The above links are from June 3rd, not sure if there are more current
versions with better support...
If you look around the SQL Thing site (
http://www.sqlthing.com) and the
above sites you should come across a number of samples and further
information.
I understand that Client Access V5R3 will include a "native" .NET Data
Provider, which should see an improvement in performance!
http://www.iseriesnetwork.com/news/nwn/story.cfm?ID=18476&channel=news
Hope this helps
Jay