maddmax
First of all: I never heard of something like this. My second thought is that your description is open to many interpretations. So please provide some more info.
For instance when you say "eclipse tells me" do you mean the indexer, in the console output or in the problem window?
I would like to see a screenshot of where you get the error. Preferably the whole eclipse window.
Have you seen this video? http://eclipse.baeyens.it/serial_demo.wmv it shows you how it works.
Which version of the eclipse plugin have you installed?
Probably unrelated: do you really need 64 bit eclipse? 32 bit has proven to be more stable.
Best regards
Jantje