I'm using Ubuntu 13.04 and sbt 0.12.4.

I'm new to sbt/Scala. Here's the list of Scala versions I have installed on my machine:

* Scala 2.9.2 -- installed by sbt, and the default version that sbt choose
* Scala 2.10.2 -- installed by myself, located in `/usr/xxx/share/scala-2.10.2`
* Scala 2.10.4 -- came with Eclipse located in `~/eclipse/osgi/xx/buddle/xxx`

I'd like to build a sbt project with `build.sbt` that says it needs version 2.10.2. After I type `sbt console`, it looks like: 

```
Getting Scala 2.10.2 ...
downloading http://repo1.maven.org/maven2/org/scala-lang/scala-compiler/2.10.2/scala-compiler-2.10.2.jar ...

```

...and gets stuck here. I waited four hours and couldn't get passed this. How can I fix it and change the default Scala version used by sbt?