Sharepoint sp2010 _Layouts mapped folder

I have a solution that can be deployed for SharePoint 2007 and SharePoint 2010. There are common files such as .css files and images. When I deploy the solution for SP2010, I use the mapped folder (_Layouts). And this folder should copy my files to the server. The fact is that I do not want to copy the same files to this folder. And I add them as a link. But Visual Studio does not want to copy files to the destination folder.