Scala: Trait Companion Object is not visible in Java

A companion object for a trait in Scala has no visibility problems in Scala:

trait ProtocolPacket extends Serializable {    
  def toByteArray: Array[Byte]
}

object ProtocolPacket {
  def getStreamType( streamBytes: Array[Byte] ) = {
    // ...
  }
}

However on Java side (e.g. gets the above in a jar), a ProtocolPacket.getStreamType is not visible. In fact a (decompiled by IDEA) source does not have a getStreamType method defined for a ProtocolPacket

EDIT:

I found similar hits on SO regarding Companion$MODULE$, but was tricked by IDEA :) as shown below:

The above compiles and runs fine (shell and/or IDEA itself), in case anybody else gets trapped.