We wanted to apply client side caching to Unified File System provided files. Basically when I hit a refresh in the browser any images stored plain in the application folder return "HTTP/1.1 304 Not Modified" but all images and files that are stored in the unified file system do not. This is attributed to the lack of the ETag header in the response. Can this be enabled in CMS 4, or perhaps has anyone worked around this? The client has a fairly high load on the servers and I was pondering this as one of the factors potentially improving our performance.