New Dell Laptop with Internet Security 2009 - Can I install on 3 PCs or just the Dell?

I have just received a new Dell Vostro 1520 laptop. I ordered it with 36 month Norton Internet Security as I was attracted by the offer of being able to install it on up to 3 machines (I have another laptop and a desktop) … refer here for the DELL description of what you get when you option up to Norton Internet Security - http://i.dell.com/images/global/products/314x314/fy10_norton_internet_security.jpg .

However, I have just checked my Norton Account and it says PROTECTION FOR 1 PC … REMAINING ACTIVATIONS NONE. This is before I have attempted to install on my other existing laptop and desktop.

Can someone please clarify whether I have misunderstood the DELL offer (maybe it is only a single license … not the 3 licenses they advertise??) or am I perhaps misreading the Norton Account information?

Many thanks,
Scott