SBT project import java.lang.RuntimeException webplugin UnsupportedClassVer.. Follow

Hi
Help me understand what's wrong with my project configuration

Could not import Lift-web SBT project

env and plugin

MacOs
Idea IU-135 690
sbt 0.13.1
scala 2.10.4
java 7.055
"com.earldouglas" % "xsbt-web-plugin" % "0.7.0" plugin

Exception:

java.lang.RuntimeException: Something went wrong finding a runner
 at com.earldouglas.xsbtwebplugin.Runner$.guessRunner(Runner.scala:43)
at com.earldouglas.xsbtwebplugin.Runner$.apply(Runner.scala:22)
 at com.earldouglas.xsbtwebplugin.Container$Impl$.newRunner(Container.scala:39)...

Caused by: java.lang.UnsupportedClassVersionError: org/eclipse/jetty/server/Handler : Unsupported major.minor version 51.0

Thanks