Gas fumes from tank vent tube all the time?

So I'm flushing the cooling system as regular maintenance b/c heaven knows when the PO ever did. As I'm doing this I notice that there are fuel "fumes" visible and pungently coming out of the tube that terminates near the water pump and the coolant reservoir overflow tubes. I trace it back and it is one of the vent tubes that drains overflow gas should you over do it when you top off the tank.
This has me a bit concerned;
1. It is a potential fire hazard.
2. I'm wasting a lot of gas if this is happening all the time.

Is this normal? I doubt it but I thought I'd ask. What are the potential remedies? New gas cap gasket? Is there supposed to be an inline check valve that is perhaps missing?

Any ideas?

I've got the fairing off now if anyone has a quick fix that requires that, waiting for the system to cool down and hopefully burp before putting the tupperware back on.

 

I've noticed the same thing on my '05 after I get home from a ride. Not to say that it is suppose to do that. I would think that it would vent to the charcol canister. So... I guess I'm not much help.