unicode problem

Hi everybody,

I try to make a plot using chineese strings (unicode).
The folowing code works :

# -*- coding: utf-8 -*-
import matplotlib
matplotlib.use('WX')
import pylab as p

p.plot((1,2,3))
p.xlabel( '是最好的編程語言')
p.text(0.5,1.5,u'éçè')
p.show()

But the same code using WxAgg or TkAgg does not works (strings are not
displayed correctly). Is someone have an idea about this problem ?

Thanks.

Olivier