ok, this is the One True Way to do builds inside / outside the firewall

project/plugins.sbt

@@ -1,12 +1,25 @@
+name := "plugins"
+
+sbtResolver <<= (sbtResolver) { r =>
+  Option(System.getenv("SBT_PROXY_REPO")) map { x =>
+    Resolver.url("proxy repo for sbt", url(x))(Resolver.ivyStylePatterns)                                             
+  } getOrElse r
+}
+
+resolvers <<= (resolvers) { r =>
+  (Option(System.getenv("SBT_PROXY_REPO")) map { url =>
+    Seq("proxy-repo" at url)
+  } getOrElse {
+    r ++ Seq(
+      "twitter.com" at "http://maven.twttr.com/",
+      "scala-tools" at "http://scala-tools.org/repo-releases/",
+      "maven" at "http://repo1.maven.org/maven2/",
+      "freemarker" at "http://freemarker.sourceforge.net/maven2/"
+    )
+  }) ++ Seq("local" at ("file:" + System.getProperty("user.home") + "/.m2/repo/"))
+}
+
+externalResolvers <<= (resolvers) map identity
+
+addSbtPlugin("com.twitter" % "sbt-package-dist" % "0.99.0")
 
-resolvers ++= Option(System.getenv("SBT_PROXY_REPO")) map { url =>
-  Seq("proxy-repo" at url)
-} getOrElse {
-  Seq(
-    "twitter.com" at "http://maven.twttr.com/",
-    "scala-tools" at "http://scala-tools.org/repo-releases/",
-    "freemarker" at "http://freemarker.sourceforge.net/maven2/"
-  )
-} ++ Seq("local" at ("file:" + System.getProperty("user.home") + "/.m2/repo/"))
-
-addSbtPlugin("com.twitter" % "standard-project2" % "0.0.5")