Pattern matching zero-argument functions in scala: mystified by warning

I'm playing with scala's distributed actors. Very nice. I have a server which executes incoming function objects. For example, the client has ``` object Tasks { def foo = {Console.println("I am Foo")}; def bar = {Console.println("I am Bar");} } // In client actor... ... server ! Tasks.foo _ ... ``` And the server can pick these up and execute them with actor code like ``` react { case task:(()=>Unit) => task() ``` This all works nicely (which is very very cool indeed) but I'm mystified by a warning message output by `scalac` for the server code: ``` warning: non variable type-argument Unit in type pattern is unchecked since it is eliminated by erasure case task:(()=>Unit) => ^ ``` How can I clean this warning up ? (I'm pretty unclear on the difference between the `Unit` type, and the `()=>Unit` type of zero-argument functions. Just trying to match `task:Unit` in the `react` is warning-free, but actually doesn't match the incoming tasks.) Using Scala 2.7.5 on Debian, with Sun's Java6.