ClassNotFoundException in compileScoverageScala

[ZsoltFabok]

There is a String conversion problem with 0.5-SNAPSHOT:

Caused by: java.lang.ClassCastException: org.codehaus.groovy.runtime.GStringImpl cannot be cast to java.lang.String
    at sbt.compiler.AggressiveCompile$$anonfun$explicitBootClasspath$1.apply(AggressiveCompile.scala:181)
    at scala.collection.TraversableLike$$anonfun$dropWhile$1.apply(TraversableLike.scala:547)
    at scala.collection.Iterator$class.foreach(Iterator.scala:727)
    at scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
    at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)