check message of exception

Test Script:
----
require 'test/unit/assertions.rb'
include Test::Unit::Assertions

class ZeroDivisionError
  def self.new(message)
    42
  end
end

assert_raise(TypeError){ 1/0 }

eval.c

@@ -287,13 +287,19 @@ VALUE rb_make_backtrace(void);
 void
 rb_exc_raise(VALUE mesg)
 {
+    if (!NIL_P(mesg)) {
+	mesg = rb_make_exception(1, &mesg);
+    }
     rb_vm_raise(mesg);
     abort();
 }
 
 void
 rb_exc_fatal(VALUE mesg)
 {
+    if (!NIL_P(mesg)) {
+	mesg = rb_make_exception(1, &mesg);
+    }
     rb_vm_raise(mesg);
     abort();
 }