How do I get Eclipse to see Scala sources in a jar?

I get the follow开发者_开发知识库ing Eclipse error when browsing a binary scala jar dependency :

Source not found

The source attachment does not contain the source for the file Http.class
You can change the source attachment by clicking Change Attached Source below

The source attachment is a jar file containing the .scala source files, and clicking the button and re-navigating to the jar does nothing. Is there a way to get it to work?

Incidentally, this is a dependency brought in by using the SBT eclipse plugin, using the withSources() dependency

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You should make sure to match your package structure with your directory structure as required in java.

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Make sure that you have installed scala IDE for Eclipse Source Feature.And then you can attach sources to scala-library in eclipse for scala projects install scala IDE for Eclipse Source Feature