Possible SBT bug: http://stackoverflow.com/questions/15562310/scala-sbt-triggering-an-action-when-local-dependencies-change

Start SBT and execute ~compile, and you should enter an infinite loop:

> ~compile
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[success] Total time: 0 s, completed Mar 23, 2013 11:56:45 AM
1. Waiting for source changes... (press enter to interrupt)
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0
[warn] Potentially incompatible versions of dependencies of {file:/wg/stor6_home3/echristiansen/delme/watchdependenciesinfiniteloop/}WatchDependenciesInfiniteLoop:
[warn]    org.scala-lang: 2.10.1, 2.10.0