http://www.capic.org/resources.html?...=What+You+Sell
Read this.
It really depends on if the work was done as a "work for hire" arrangement, in which case, once you're paid for it, the person who paid for it owns it. This also applies if you create something as an employee of a company (which I assume isn't the case in this situation).
Looking at that page, it appears that as long as you didn't sign anything specifically giving up your copyright, and it isn't a commissioned photograph or portrait, you should still own the copyright to the design.
I don't believe there have been any recent changes to the copyright law that have passed because they keep getting killed by the breaks in parliament.