Autoscale AxesImage after using set_data()

Hi,

I'm trying to autoscale an AxesImage after having set new data with set_data(). I thought, the way to do it is to use Axes.relim() followed by Axes.autoscale_view(). Unfortunately, this does not work properly both with version 0.99.3 and 1.0.1.
Consider the following example (adapted from the example <http://matplotlib.sourceforge.net/examples/animation/simple_anim_gtk.html>):

import time
import numpy as np
import matplotlib
matplotlib.use('GTKAgg')

import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)
x, y = np.mgrid[0:100, 0:100]
img = ax.imshow(np.sin(0.05 * y))

def animate():
      time.sleep(3)
      x, y = np.mgrid[0:200, 0:200]
      img.set_data(np.sin(0.05 * x))
      # set_*lim works with v 0.99.3
      ax.set_xlim(0, 200)
      ax.set_ylim(0, 200)
      # ax.relim()
      # ax.autoscale_view()
      fig.canvas.draw()
      return False

import gobject
gobject.idle_add(animate)
plt.show()

I want the plot to show the 200x200 image after the update, with the correct ticks showing. But what I get is the following:

Using set_xlim() and set_ylim() works, but only for version 0.99.3.
With version 1.0.1 the axes show a range of 200x200, and the new image data is used, but the new 200x200 image is shrunk to a 100x100 region.

Using relim() and autoscale_view(), which is what I thought the correct way to do it, also does not work:
With version 0.99.3 it does nothing, it does no autoscaling at all. With version 1.0.1 the new image is shown completely, but the axes ticks still show 0..100 instead of 0..200

Thanks for you help,
Christoph