diff --git a/compile/interface/src/main/scala/xsbt/Compat.scala b/compile/interface/src/main/scala/xsbt/Compat.scala
index 5b8c3983b..9f9fb247c 100644
--- a/compile/interface/src/main/scala/xsbt/Compat.scala
+++ b/compile/interface/src/main/scala/xsbt/Compat.scala
@@ -45,15 +45,10 @@ abstract class Compat {
   val Nullary = global.NullaryMethodType
   val ScalaObjectClass = definitions.ScalaObjectClass
 
-  // `afterPostErasure` doesn't exist in Scala < 2.10
-  implicit def withAfterPostErasure(global: Global): WithAfterPostErasure = new WithAfterPostErasure(global)
-  class WithAfterPostErasure(global: Global) {
-    def afterPostErasure[T](op: => T): T = op
-  }
-  // `exitingPostErasure` was called `afterPostErasure` in 2.10
-  implicit def withExitingPostErasure(global: Global): WithExitingPostErasure = new WithExitingPostErasure(global)
-  class WithExitingPostErasure(global: Global) {
-    def exitingPostErasure[T](op: => T): T = global afterPostErasure op
+  // `transformedType` doesn't exist in Scala < 2.10
+  implicit def withTransformedType(global: Global): WithTransformedType = new WithTransformedType(global)
+  class WithTransformedType(global: Global) {
+    def transformedType(tpe: Type): Type = tpe
   }
 
   private[this] final class MiscCompat {
diff --git a/compile/interface/src/main/scala/xsbt/ExtractAPI.scala b/compile/interface/src/main/scala/xsbt/ExtractAPI.scala
index 172f8f090..31389218b 100644
--- a/compile/interface/src/main/scala/xsbt/ExtractAPI.scala
+++ b/compile/interface/src/main/scala/xsbt/ExtractAPI.scala
@@ -225,10 +225,10 @@ class ExtractAPI[GlobalType <: CallbackGlobal](val global: GlobalType,
 
       def build(t: Type, typeParams: Array[xsbti.api.TypeParameter], valueParameters: List[xsbti.api.ParameterList]): List[xsbti.api.Def] =
         {
-          def parameterList(syms: List[Symbol]): xsbti.api.ParameterList =
+          def parameterList(syms: List[Symbol], erase: Boolean = false): xsbti.api.ParameterList =
             {
               val isImplicitList = syms match { case head :: _ => isImplicit(head); case _ => false }
-              new xsbti.api.ParameterList(syms.map(parameterS).toArray, isImplicitList)
+              new xsbti.api.ParameterList(syms.map(parameterS(erase)).toArray, isImplicitList)
             }
           t match {
             case PolyType(typeParams0, base) =>
@@ -249,7 +249,7 @@ class ExtractAPI[GlobalType <: CallbackGlobal](val global: GlobalType,
                 build(resultType, typeParams, parameterList(params) :: valueParameters)
               val afterErasure  =
                 if (inspectPostErasure)
-                  build(resultType, typeParams, global exitingPostErasure (parameterList(mType.params) :: valueParameters))
+                  build(resultType, typeParams, parameterList(mType.params, erase = true) :: valueParameters)
                 else
                   Nil
 
@@ -277,7 +277,7 @@ class ExtractAPI[GlobalType <: CallbackGlobal](val global: GlobalType,
               val beforeErasure = makeDef(processType(in, dropConst(returnType)))
               val afterErasure =
                 if (inspectPostErasure) {
-                  val erasedReturn = dropConst(global exitingPostErasure viewer(in).memberInfo(s)) map {
+                  val erasedReturn = dropConst(global.transformedType(viewer(in).memberInfo(s))) map {
                     case MethodType(_, r) => r
                     case other            => other
                   }
@@ -287,8 +287,10 @@ class ExtractAPI[GlobalType <: CallbackGlobal](val global: GlobalType,
               beforeErasure :: afterErasure
           }
         }
-      def parameterS(s: Symbol): xsbti.api.MethodParameter =
-        makeParameter(simpleName(s), s.info, s.info.typeSymbol, s)
+      def parameterS(erase: Boolean)(s: Symbol): xsbti.api.MethodParameter = {
+        val tp = if (erase) global.transformedType(s.info) else s.info
+        makeParameter(simpleName(s), tp, tp.typeSymbol, s)
+      }
 
       // paramSym is only for 2.8 and is to determine if the parameter has a default
       def makeParameter(name: String, tpe: Type, ts: Symbol, paramSym: Symbol): xsbti.api.MethodParameter =
diff --git a/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A0.scala b/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A0.scala
new file mode 100644
index 000000000..cc6a53b6a
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A0.scala
@@ -0,0 +1,11 @@
+package example
+
+class A {
+  case class B(x: Int)
+  def c = B
+}
+object A {
+  def main(args: Array[String]): Unit = {
+    (new A).c
+  }
+}
diff --git a/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A1.scala b/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A1.scala
new file mode 100644
index 000000000..e71b1ef17
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/nested-case-class/changes/A1.scala
@@ -0,0 +1,13 @@
+package example
+
+class VC(val self: Int) extends AnyVal
+
+class A {
+  case class B(x: VC)
+  def c = B
+}
+object A {
+  def main(args: Array[String]): Unit = {
+    (new A).c
+  }
+}
\ No newline at end of file
diff --git a/sbt/src/sbt-test/source-dependencies/nested-case-class/test b/sbt/src/sbt-test/source-dependencies/nested-case-class/test
new file mode 100644
index 000000000..28ed70321
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/nested-case-class/test
@@ -0,0 +1,6 @@
+$ copy-file changes/A0.scala A.scala
+> run
+
+# The same test case, but involving value classes
+$ copy-file changes/A1.scala A.scala
+> run