This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
@Autowired works differently for collections. It would work if for example you did this
In this case your List would contain 2 beans of type ThirdParty service one with a name instance1 and one instance2. Basically what it does is scan the context for dependencies of that type and adds them to the collection.
If you want to do what you are doing you should use the @Resource annotation on your list.