UFL that implements this function is missing

Hello. I am writing a VB.NET 2008 app using the CrystalReportViewer component. A decade ago I wrote something similar in VB6, and I want to replace it (but I'm doing a rewrite not a port).

Everything works like a charm, except that some of my reports use functions from a UFL (named u2lsvrep.dll) that we wrote years ago. Those reports give me the following error:

"UFL 'u2lsvrep.dll' that implements this function is missing."

I have that dll. Where do I have to put it, or what else do I have to do, in order for my program to be able to display reports that use functions from it?

Any help is greatly appreciated, thanks.

For XI Release 2 we put custom UFLs under

C:\Program Files\Business Objects\Common\3.5