diff --git a/ChangeLog b/ChangeLog
index 32d53da55c..415e99ca5b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Sun Nov 16 04:41:33 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* eval.c (eval): do not re-raise exception to avoid unnecessary
+	  exception copying, instead modify exception and internal
+	  information to adjust eval().
+
+	* eval.c (backtrace): can return the current frame information
+	  only if lev < -1.
+
 Sat Nov 15 22:16:42 2003  GOTOU Yuuzou  <gotoyuzo@notwork.org>
 
 	* /ext/openssl/ossl_x509ext.c (ossl_x509extfactory_create_ext):
diff --git a/error.c b/error.c
index 2baf3b1ba7..b5b14decae 100644
--- a/error.c
+++ b/error.c
@@ -479,8 +479,9 @@ name_err_initialize(argc, argv, self)
     VALUE *argv;
     VALUE self;
 {
-    VALUE name = (argc > 1) ? argv[--argc] : Qnil;
+    VALUE name;
 
+    name = (argc > 1) ? argv[--argc] : Qnil;
     exc_initialize(argc, argv, self);
     rb_iv_set(self, "name", name);
     return self;
diff --git a/eval.c b/eval.c
index 64fa28bd98..4d3fd66b7f 100644
--- a/eval.c
+++ b/eval.c
@@ -1328,7 +1328,6 @@ void rb_exec_end_proc _((void));
 static void
 ruby_finalize_0()
 {
-    ruby_errinfo = 0;
     PUSH_TAG(PROT_NONE);
     if (EXEC_TAG() == 0) {
 	rb_trap_exit();
@@ -4719,6 +4718,58 @@ static int last_call_status;
 #define CSTAT_VCALL 4
 #define CSTAT_SUPER 8
 
+static VALUE
+name_err_to_s(exc)
+    VALUE exc;
+{
+    VALUE mesg = rb_attr_get(exc, rb_intern("mesg"));
+    ID id_recv = rb_intern("recv");
+
+    if (NIL_P(mesg)) return rb_class_path(CLASS_OF(exc));
+    if (rb_ivar_defined(exc, id_recv)) {
+	char buf[BUFSIZ];
+	char *desc = "";
+	volatile VALUE d = 0;
+	int noclass;
+	VALUE obj = rb_ivar_get(exc, id_recv);
+	int state;
+
+	switch (TYPE(obj)) {
+	  case T_NIL:
+	    desc = "nil";
+	    break;
+	  case T_TRUE:
+	    desc = "true";
+	    break;
+	  case T_FALSE:
+	    desc = "false";
+	    break;
+	  default:
+	    PUSH_TAG(PROT_NONE);
+	    if ((state = EXEC_TAG()) == 0) {
+		d = rb_inspect(obj);
+	    }
+	    POP_TAG();
+	    if (!d || RSTRING(d)->len > 65) {
+		d = rb_any_to_s(obj);
+	    }
+	    break;
+	}
+	if (d) {
+	    desc = RSTRING(d)->ptr;
+	}
+	noclass = (!desc || desc[0]=='#');
+	snprintf(buf, BUFSIZ, RSTRING(mesg)->ptr, desc,
+		 noclass ? "" : ":",
+		 noclass ? "" : rb_obj_classname(obj));
+	mesg = rb_str_new2(buf);
+	rb_iv_set(exc, "mesg", mesg);
+	st_delete(ROBJECT(exc)->iv_tbl, (st_data_t*)&id_recv, 0);
+    }
+    if (OBJ_TAINTED(exc)) OBJ_TAINT(mesg);
+    return mesg;
+}
+
 static VALUE
 rb_method_missing(argc, argv, obj)
     int argc;
@@ -4727,11 +4778,8 @@ rb_method_missing(argc, argv, obj)
 {
     ID id;
     VALUE exc = rb_eNoMethodError;
-    volatile VALUE d = 0;
     char *format = 0;
-    char *desc = "";
     NODE *cnode = ruby_current_node;
-    int state;
 
     if (argc == 0 || !SYMBOL_P(argv[0])) {
 	rb_raise(rb_eArgError, "no id given");
@@ -4741,64 +4789,37 @@ rb_method_missing(argc, argv, obj)
 
     id = SYM2ID(argv[0]);
 
-    switch (TYPE(obj)) {
-      case T_NIL:
-	desc = "nil";
-	break;
-      case T_TRUE:
-	desc = "true";
-	break;
-      case T_FALSE:
-	desc = "false";
-	break;
-      default:
-	PUSH_TAG(PROT_NONE);
-	if ((state = EXEC_TAG()) == 0) {
-	    d = rb_inspect(obj);
-	}
-	POP_TAG();
-	if (!d || RSTRING(d)->len > 65) {
-	    d = rb_any_to_s(obj);
-	}
-	break;
-    }
-    if (d) {
-	desc = RSTRING(d)->ptr;
-    }
-
     if (last_call_status & CSTAT_PRIV) {
-	format = "private method `%s' called for %s%s%s";
+	format = "private method `%s' called for %%s%%s%%s";
     }
     else if (last_call_status & CSTAT_PROT) {
-	format = "protected method `%s' called for %s%s%s";
+	format = "protected method `%s' called for %%s%%s%%s";
     }
     else if (last_call_status & CSTAT_VCALL) {
-	format = "undefined local variable or method `%s' for %s%s%s";
+	format = "undefined local variable or method `%s' for %%s%%s%%s";
 	exc = rb_eNameError;
     }
     else if (last_call_status & CSTAT_SUPER) {
 	format = "super: no superclass method `%s'";
     }
     if (!format) {
-	format = "undefined method `%s' for %s%s%s";
+	format = "undefined method `%s' for %%s%%s%%s";
     }
 
     ruby_current_node = cnode;
     {
 	char buf[BUFSIZ];
-	int noclass = (!desc || desc[0]=='#');
 	int n = 0;
 	VALUE args[3];
 
-	snprintf(buf, BUFSIZ, format, rb_id2name(id),
-		 desc, noclass ? "" : ":",
-		 noclass ? "" : rb_obj_classname(obj));
+	snprintf(buf, BUFSIZ, format, rb_id2name(id));
 	args[n++] = rb_str_new2(buf);
 	args[n++] = argv[0];
 	if (exc == rb_eNoMethodError) {
 	    args[n++] = rb_ary_new4(argc-1, argv+1);
 	}
 	exc = rb_class_new_instance(n, args, exc);
+	rb_iv_set(exc, "recv", obj);
 	ruby_frame = ruby_frame->prev; /* pop frame for "method_missing" */
 	rb_exc_raise(exc);
     }
@@ -5357,6 +5378,7 @@ backtrace(lev)
 	    snprintf(buf, BUFSIZ, "%s:%d", ruby_sourcefile, ruby_sourceline);
 	}
 	rb_ary_push(ary, rb_str_new2(buf));
+	if (lev < -1) return ary;
     }
     else {
 	while (lev-- > 0) {
@@ -5557,20 +5579,13 @@ eval(self, src, scope, file, line)
     ruby_set_current_source();
     if (state) {
 	if (state == TAG_RAISE) {
-	    VALUE err, errat, mesg;
-
-	    mesg = rb_obj_as_string(ruby_errinfo);
 	    if (strcmp(file, "(eval)") == 0) {
-		if (ruby_sourceline > 1) {
-		    errat = get_backtrace(ruby_errinfo);
-		    err = rb_str_dup(RARRAY(errat)->ptr[0]);
-		    rb_str_cat2(err, ": ");
-		    rb_str_append(err, mesg);
-		}
-		else {
-		    err = mesg;
-		}
-		rb_exc_raise(rb_funcall(ruby_errinfo, rb_intern("exception"), 1, err));
+		VALUE mesg, errat;
+
+		errat = get_backtrace(ruby_errinfo);
+		mesg  = rb_obj_as_string(ruby_errinfo);
+		rb_str_update(mesg, 0, 0, RARRAY(errat)->ptr[0]);
+		RARRAY(errat)->ptr[0] = RARRAY(backtrace(-2))->ptr[0];
 	    }
 	    rb_exc_raise(ruby_errinfo);
 	}
@@ -6757,6 +6772,9 @@ Init_load()
 
     ruby_dln_librefs = rb_ary_new();
     rb_global_variable(&ruby_dln_librefs);
+
+    /* not really a right place */
+    rb_define_method(rb_eNameError, "to_s", name_err_to_s, 0);
 }
 
 static void