Aló, Éric.

>I have to use Java classes from a VB.Net application. I never did that. How
>can I use these classes ?
>
>The Java library was provided to me by FundServ. Anyone know it?
>
>The library is provided as .jar file.

Some pointers:
http://www.devx.com/interop/Door/18896
http://msdn.microsoft.com/vstudio/java/interop/default.aspx
http://www.jnbridge.com/

And the (already) canonical book:
http://www.amazon.com/gp/product/0735619220/ref=bxgy_cc_img_b/102-2253985-7179361?%5Fencoding=UTF8
(you don't need to buy it, you can ask Guy to let you check it to have a general idea, or have a quick read at Amazon).

Best regards,