NoSuchMethodError when attempting to implicitly convert a java to scala collection

I started to receive this kind of error in my code:

Message:
java.lang.NoSuchMethodError:scala.collection.JavaConversions
$.asScalaSet(Ljava/util开发者_StackOverflow中文版/Set;)Lscala/collection/mutable/Set

and then I see a long screen of stacktrace of uninteresting nature, which is triggered on this piece of code:

edited.authors.toSeq

where authors is a java.lang.Set. Does anybody know why is this happening? It's a runtime failure and not a compile one.

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You are using a library which has been compiled with 2.8.1 from the 2.8.0 runtime