Point user to existing node with the same field value

I have site setup when products are submitted by users. Thanks to this great module I can check if product already exists in the DB so it won't be added twice. I check by product's Link type CCK field ( products have unique URLs by their nature) and it seems to work ok. But I want to warn user more clearly that product he's trying to add already exists and point him to existing node with same URL in Link field.
Would be great if that feature was added, it seems like it's common setup type.