Common Rail Diesel Fault

[rhinochopig]

A bit of advice needed please. I've just bought a S/H diesel x-trail and after a number of issues, I've become a little paranoid about identifying potential problems whilst It's still under warranty. So, I've been going over it with a fine toothed comb and have found this...

Should there be any fluid (diesel) on the surface of the common rail. Particularly in the well formed where the pipes run into the bolt. The pic is not my car, but shows a similar set-up.