@Sn3ak:
Obscurity is not security. This is a bad line of thinking, especially if you wish to sell to Enterprises. Sure, hiding as much as possible from external attackers is nice but hiding from your CS department (or yourself) is generally not a good practice.
This is not security by obscurity. It's reducing unnecessary information exposure. If you rely on the device itself to tell you what version something is, you need to have a proper mechanism setup and in place to do that internally (e.g. SNMP or other means of querying the device).
Being able to determine the OS based on network behavior or daemon responses is not a reliable detection mechanism, and being able to do so is a problem, not a solution. I wouldn't go so far as to say it's a security issue if you can identify the OS, but it's still better if it's not accurately discernible.