diff -r 64d41533dc9e -r 532f41763bc9 langtools/src/share/classes/com/sun/tools/javac/comp/Infer.java
--- a/langtools/src/share/classes/com/sun/tools/javac/comp/Infer.java	Wed Jan 18 18:26:36 2012 -0800
+++ b/langtools/src/share/classes/com/sun/tools/javac/comp/Infer.java	Tue Jan 24 17:52:02 2012 +0000
@@ -34,6 +34,7 @@
 import com.sun.tools.javac.code.Type.*;
 import com.sun.tools.javac.code.Type.ForAll.ConstraintKind;
 import com.sun.tools.javac.code.Symbol.*;
+import com.sun.tools.javac.comp.Resolve.InapplicableMethodException;
 import com.sun.tools.javac.comp.Resolve.VerboseResolutionMode;
 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
 
@@ -84,7 +85,7 @@
 
     }
 
-    public static class InferenceException extends Resolve.InapplicableMethodException {
+    public static class InferenceException extends InapplicableMethodException {
         private static final long serialVersionUID = 0;
 
         InferenceException(JCDiagnostic.Factory diags) {
@@ -287,6 +288,18 @@
         }
     }
 
+    Type asUndetType(Type t, List<Type> undetvars) {
+        return types.subst(t, inferenceVars(undetvars), undetvars);
+    }
+
+    List<Type> inferenceVars(List<Type> undetvars) {
+        ListBuffer<Type> tvars = ListBuffer.lb();
+        for (Type uv : undetvars) {
+            tvars.append(((UndetVar)uv).qtype);
+        }
+        return tvars.toList();
+    }
+
 /***************************************************************************
  * Exported Methods
  ***************************************************************************/
@@ -372,62 +385,11 @@
                                   final Warner warn) throws InferenceException {
         //-System.err.println("instantiateMethod(" + tvars + ", " + mt + ", " + argtypes + ")"); //DEBUG
         List<Type> undetvars = Type.map(tvars, fromTypeVarFun);
-        List<Type> formals = mt.argtypes;
-        //need to capture exactly once - otherwise subsequent
-        //applicability checks might fail
-        final List<Type> capturedArgs = types.capture(argtypes);
-        List<Type> actuals = capturedArgs;
-        List<Type> actualsNoCapture = argtypes;
-        // instantiate all polymorphic argument types and
-        // set up lower bounds constraints for undetvars
-        Type varargsFormal = useVarargs ? formals.last() : null;
-        if (varargsFormal == null &&
-                actuals.size() != formals.size()) {
-            throw unambiguousNoInstanceException
-                .setMessage("infer.arg.length.mismatch");
-        }
-        while (actuals.nonEmpty() && formals.head != varargsFormal) {
-            Type formal = formals.head;
-            Type actual = actuals.head.baseType();
-            Type actualNoCapture = actualsNoCapture.head.baseType();
-            if (actual.tag == FORALL)
-                actual = instantiateArg((ForAll)actual, formal, tvars, warn);
-            Type undetFormal = types.subst(formal, tvars, undetvars);
-            boolean works = allowBoxing
-                ? types.isConvertible(actual, undetFormal, warn)
-                : types.isSubtypeUnchecked(actual, undetFormal, warn);
-            if (!works) {
-                throw unambiguousNoInstanceException
-                    .setMessage("infer.no.conforming.assignment.exists",
-                                tvars, actualNoCapture, formal);
-            }
-            formals = formals.tail;
-            actuals = actuals.tail;
-            actualsNoCapture = actualsNoCapture.tail;
-        }
+        //final List<Type> capturedArgs = types.capture(argtypes);
 
-        if (formals.head != varargsFormal) // not enough args
-            throw unambiguousNoInstanceException.setMessage("infer.arg.length.mismatch");
-
-        // for varargs arguments as well
-        if (useVarargs) {
-            Type elemType = types.elemtype(varargsFormal);
-            Type elemUndet = types.subst(elemType, tvars, undetvars);
-            while (actuals.nonEmpty()) {
-                Type actual = actuals.head.baseType();
-                Type actualNoCapture = actualsNoCapture.head.baseType();
-                if (actual.tag == FORALL)
-                    actual = instantiateArg((ForAll)actual, elemType, tvars, warn);
-                boolean works = types.isConvertible(actual, elemUndet, warn);
-                if (!works) {
-                    throw unambiguousNoInstanceException
-                        .setMessage("infer.no.conforming.assignment.exists",
-                                    tvars, actualNoCapture, elemType);
-                }
-                actuals = actuals.tail;
-                actualsNoCapture = actualsNoCapture.tail;
-            }
-        }
+        final List<Type> capturedArgs =
+                rs.checkRawArgumentsAcceptable(env, undetvars, argtypes, mt.getParameterTypes(),
+                    allowBoxing, useVarargs, warn, new InferenceCheckHandler(undetvars));
 
         // minimize as yet undetermined type variables
         for (Type t : undetvars)
@@ -503,6 +465,31 @@
     }
     //where
 
+        /** inference check handler **/
+        class InferenceCheckHandler implements Resolve.MethodCheckHandler {
+
+            List<Type> undetvars;
+
+            public InferenceCheckHandler(List<Type> undetvars) {
+                this.undetvars = undetvars;
+            }
+
+            public InapplicableMethodException arityMismatch() {
+                return unambiguousNoInstanceException.setMessage("infer.arg.length.mismatch");
+            }
+            public InapplicableMethodException argumentMismatch(boolean varargs, Type found, Type expected) {
+                String key = varargs ?
+                    "infer.varargs.argument.mismatch" :
+                    "infer.no.conforming.assignment.exists";
+                return unambiguousNoInstanceException.setMessage(key,
+                        inferenceVars(undetvars), found, expected);
+            }
+            public InapplicableMethodException inaccessibleVarargs(Symbol location, Type expected) {
+                return unambiguousNoInstanceException.setMessage("inaccessible.varargs.type",
+                        expected, Kinds.kindName(location), location);
+            }
+        }
+
         /**
          * A delegated type representing a partially uninferred method type.
          * The return type of a partially uninferred method type is a ForAll
@@ -572,7 +559,7 @@
                 rs.checkRawArgumentsAcceptable(env, actuals, formals,
                        allowBoxing, useVarargs, warn);
             }
-            catch (Resolve.InapplicableMethodException ex) {
+            catch (InapplicableMethodException ex) {
                 // inferred method is not applicable
                 throw invalidInstanceException.setMessage(ex.getDiagnostic());
             }