Extending an attribute with a trait

Stevan, other Moose-people,

I'm having a problem using an attribute trait in a subclass.  If I
have an attribute in the superclass, then extend that attribute in the
subclass by adding a trait, it complains about the behavior I'm adding
with: Illegal inherited options => (foo).  Since I made "foo"
required, then I can't add the trait without it complaining: Attribute
(foo) is required.

The following code demonstrates this issue.  Is there a workaround?

-----------------------

package Demo::Meta::Attribute::Trait::Foo;
use Moose::Role;

has foo => (
    is => 'rw',
    isa => 'Str',
    required => 1,
);

package Moose::Meta::Attribute::Custom::Trait::Foo;
sub register_implementation { 'Demo::Meta::Attribute::Trait::Foo' }

package MyClass;
use Moose;

has 'one' => (
    is => 'rw',
    isa => 'Str',
    traits => [qw/Foo/],
    foo => 'bar',
);

has 'two' => (
    is => 'rw',
    isa => 'Str',
);

package MySubClass;
use Moose;
extends 'MyClass';

has '+two' => (
    traits => [qw/Foo/],
    foo => 'baz',
);

package main;
use strict;
use warnings;

my $o = MySubClass->new();

1;