scala - tasks and dependencies in Play! framework 2.3 -

i'm trying task in play! that:

in build.sbt

lazy val hellotask = taskkey[unit]("hello", "description bla bla")  hellotask := {   mypakage.myclass.update   println("well done") }  (compile in compile) <<= (compile in compile)  dependson hellotask 

but when execute

$ activator tasks 

it doesn't show "hello" task runs

$ activator hello 

the problem when add references classes (mypakage.myclass.update in example isn't found)

thanks lot

despite documentation says, can't seem list taskkey, either. works inputkey instead of taskkey.

lazy val hellotask = inputkey[unit]("hello", "description bla bla")  hellotask := {   println("well done") } 

the other problem dependencies in build.sbt need resolved via sbt plugins. mypakage.myclass must split separate project in order used in build.