Eclipse StatEt echo every line twice?

Question

Here is the code I tried to send to R console in Eclipse:

distuni = setRefClass("DistUniform", 
        c("a", "b"),
        methods = list(
                mean = function() {
                    (a+b)/2
                }
                )
        )

Here is a screenshot of the result:

As you can see, every line is echoed twice, very annoying. Any suggestions how to solve this?