diff --git a/src/main/scala/sbt/LineReader.scala b/src/main/scala/sbt/LineReader.scala
index 2bd655bef..558b08936 100644
--- a/src/main/scala/sbt/LineReader.scala
+++ b/src/main/scala/sbt/LineReader.scala
@@ -9,6 +9,7 @@ trait LineReader extends NotNull
 }
 class Completors(val projectAction: String, val projectNames: Iterable[String],
 	val generalCommands: Iterable[String], val propertyActions: Iterable[String],
+	val specificPrefix: String, val scalaVersions: Iterable[String],
 	val prefixes: Iterable[String]) extends NotNull
 import jline.ConsoleReader
 abstract class JLine extends LineReader
@@ -102,7 +103,12 @@ class JLineReader(historyPath: Option[Path], completors: Completors, log: Logger
 	private def propertyCompletor(propertyNames: Iterable[String]) =
 		simpleArgumentCompletor(propertyActions, propertyNames)
 	private def prefixedCompletor(baseCompletor: Completor) =
-		singleArgumentCompletor(simpleCompletor(prefixes.toList.toArray[String]), baseCompletor)
+		singleArgumentCompletor(simpleCompletor(prefixes), baseCompletor)
+	private def specificCompletor(baseCompletor: Completor) =
+	{
+		val specific = simpleCompletor(specificPrefix :: Nil) // TODO
+		new ArgumentCompletor( Array( specific, simpleCompletor(scalaVersions), baseCompletor ) )
+	}
 	def setVariableCompletions(taskNames: Iterable[String], propertyNames: Iterable[String], extra: Iterable[(String, Iterable[String])] )
 	{
 		import scala.collection.immutable.TreeSet
@@ -110,6 +116,6 @@ class JLineReader(historyPath: Option[Path], completors: Completors, log: Logger
 		val extraCompletors = for( (first, repeat) <- extra) yield repeatedArgumentCompletor(simpleCompletor(first :: Nil), simpleCompletor(repeat))
 		val baseCompletors = generalCompletor :: taskCompletor :: projectCompletor :: propertyCompletor(propertyNames) :: extraCompletors.toList
 		val baseCompletor = new MultiCompletor(baseCompletors.toArray)
-		completor.setCompletors( Array(baseCompletor, prefixedCompletor(baseCompletor)) )
+		completor.setCompletors( Array(baseCompletor, prefixedCompletor(baseCompletor), specificCompletor(baseCompletor)) )
 	}
 }
\ No newline at end of file
diff --git a/src/main/scala/sbt/Main.scala b/src/main/scala/sbt/Main.scala
index d3d573d8d..918114f0a 100755
--- a/src/main/scala/sbt/Main.scala
+++ b/src/main/scala/sbt/Main.scala
@@ -258,7 +258,7 @@ class xMain extends xsbti.AppMain
 	object SpecificBuild
 	{
 		import java.util.regex.Pattern.{compile,quote}
-		val pattern = compile(quote(SpecificBuildPrefix) + """(\S+)\s*(.*)""")
+		val pattern = compile(quote(SpecificBuildPrefix) + """\s*(\S+)\s*(.*)""")
 		def unapply(s: String) =
 		{
 			val m = pattern.matcher(s)
@@ -313,7 +313,8 @@ class xMain extends xsbti.AppMain
 	{
 		val projectNames = baseProject.projectClosure.map(_.name)
 		val prefixes = ContinuousExecutePrefix :: CrossBuildPrefix :: Nil
-		val completors = new Completors(ProjectAction, projectNames, interactiveCommands, List(GetAction, SetAction), prefixes)
+		val scalaVersions = baseProject.crossScalaVersions ++ Seq(baseProject.defScalaVersion.value)
+		val completors = new Completors(ProjectAction, projectNames, interactiveCommands, List(GetAction, SetAction), SpecificBuildPrefix, scalaVersions, prefixes)
 		val reader = new JLineReader(baseProject.historyPath, completors, baseProject.log)
 		val methodCompletions = for( (name, method) <- project.methods) yield (name, method.completions)
 		reader.setVariableCompletions(project.taskNames, project.propertyNames, methodCompletions)
@@ -365,7 +366,7 @@ class xMain extends xsbti.AppMain
 
 	/** The list of all available commands at the interactive prompt in addition to the tasks defined
 	* by a project.*/
-	protected def interactiveCommands: Iterable[String] = basicCommands.toList ++ logLevels.toList
+	protected def interactiveCommands: Iterable[String] = basicCommands.toList ++ logLevels.toList ++ TerminateActions
 	/** The list of logging levels.*/
 	private def logLevels: Iterable[String] = TreeSet.empty[String] ++ Level.levels.map(_.toString)
 	/** The list of all interactive commands other than logging level.*/