--- a/src/share/vm/opto/cfgnode.cpp	Thu Feb 26 19:59:04 2009 -0500
+++ b/src/share/vm/opto/cfgnode.cpp	Wed Jan 14 14:12:00 2009 -0800
@@ -858,12 +858,18 @@
   // convert the one to the other.
   const TypePtr* ttp = _type->make_ptr();
   const TypeInstPtr* ttip = (ttp != NULL) ? ttp->isa_instptr() : NULL;
+  const TypeKlassPtr* ttkp = (ttp != NULL) ? ttp->isa_klassptr() : NULL;
   bool is_intf = false;
   if (ttip != NULL) {
     ciKlass* k = ttip->klass();
     if (k->is_loaded() && k->is_interface())
       is_intf = true;
   }
+  if (ttkp != NULL) {
+    ciKlass* k = ttkp->klass();
+    if (k->is_loaded() && k->is_interface())
+      is_intf = true;
+  }
 
   // Default case: merge all inputs
   const Type *t = Type::TOP;        // Merged type starting value
@@ -921,6 +927,8 @@
     // uplift the type.
     if( !t->empty() && ttip && ttip->is_loaded() && ttip->klass()->is_interface() )
       { assert(ft == _type, ""); } // Uplift to interface
+    else if( !t->empty() && ttkp && ttkp->is_loaded() && ttkp->klass()->is_interface() )
+      { assert(ft == _type, ""); } // Uplift to interface
     // Otherwise it's something stupid like non-overlapping int ranges
     // found on dying counted loops.
     else
@@ -936,6 +944,7 @@
     // because the type system doesn't interact well with interfaces.
     const TypePtr *jtp = jt->make_ptr();
     const TypeInstPtr *jtip = (jtp != NULL) ? jtp->isa_instptr() : NULL;
+    const TypeKlassPtr *jtkp = (jtp != NULL) ? jtp->isa_klassptr() : NULL;
     if( jtip && ttip ) {
       if( jtip->is_loaded() &&  jtip->klass()->is_interface() &&
           ttip->is_loaded() && !ttip->klass()->is_interface() ) {
@@ -945,6 +954,14 @@
         jt = ft;
       }
     }
+    if( jtkp && ttkp ) {
+      if( jtkp->is_loaded() &&  jtkp->klass()->is_interface() &&
+          ttkp->is_loaded() && !ttkp->klass()->is_interface() ) {
+        assert(ft == ttkp->cast_to_ptr_type(jtkp->ptr()) ||
+               ft->isa_narrowoop() && ft->make_ptr() == ttkp->cast_to_ptr_type(jtkp->ptr()), "");
+        jt = ft;
+      }
+    }
     if (jt != ft && jt->base() == ft->base()) {
       if (jt->isa_int() &&
           jt->is_int()->_lo == ft->is_int()->_lo &&

--- a/src/share/vm/opto/type.cpp	Thu Feb 26 19:59:04 2009 -0500
+++ b/src/share/vm/opto/type.cpp	Wed Jan 14 14:12:00 2009 -0800
@@ -2471,6 +2471,8 @@
   const Type* ft = join(kills);
   const TypeInstPtr* ftip = ft->isa_instptr();
   const TypeInstPtr* ktip = kills->isa_instptr();
+  const TypeKlassPtr* ftkp = ft->isa_klassptr();
+  const TypeKlassPtr* ktkp = kills->isa_klassptr();
 
   if (ft->empty()) {
     // Check for evil case of 'this' being a class and 'kills' expecting an
@@ -2484,6 +2486,8 @@
     // uplift the type.
     if (!empty() && ktip != NULL && ktip->is_loaded() && ktip->klass()->is_interface())
       return kills;             // Uplift to interface
+    if (!empty() && ktkp != NULL && ktkp->klass()->is_loaded() && ktkp->klass()->is_interface())
+      return kills;             // Uplift to interface
 
     return Type::TOP;           // Canonical empty value
   }
@@ -2499,6 +2503,12 @@
     // Happens in a CTW of rt.jar, 320-341, no extra flags
     return ktip->cast_to_ptr_type(ftip->ptr());
   }
+  if (ftkp != NULL && ktkp != NULL &&
+      ftkp->is_loaded() &&  ftkp->klass()->is_interface() &&
+      ktkp->is_loaded() && !ktkp->klass()->is_interface()) {
+    // Happens in a CTW of rt.jar, 320-341, no extra flags
+    return ktkp->cast_to_ptr_type(ftkp->ptr());
+  }
 
   return ft;
 }

--- a/src/share/vm/opto/type.hpp	Thu Feb 26 19:59:04 2009 -0500
+++ b/src/share/vm/opto/type.hpp	Wed Jan 14 14:12:00 2009 -0800
@@ -882,6 +882,8 @@
 public:
   ciSymbol* name()  const { return _klass->name(); }
 
+  bool  is_loaded() const { return _klass->is_loaded(); }
+
   // ptr to klass 'k'
   static const TypeKlassPtr *make( ciKlass* k ) { return make( TypePtr::Constant, k, 0); }
   // ptr to klass 'k' with offset