TkAgg vs. GTKAgg ioff cla behavior

the GTKAgg backend does not show the plot of y2.

On my system I get the plot of y2 (cos, not sin) -- here is the
complete script I am using and the --verbose-helpful output below

Example script:

  from pylab import *

verbose helpful output:

  matplotlib data path /usr/lib/python2.4/site-packages/matplotlib/mpl-data
  loaded rc file /home/jdhunter/.matplotlib/matplotlibrc
  matplotlib version 0.87.2svn
  verbose.level helpful
  interactive is False
  platform is linux2
  numerix numpy
  font search path ['/usr/lib/python2.4/site-packages/matplotlib/mpl-data']
  loaded ttfcache file /home/jdhunter/.matplotlib/ttffont.cache
  backend GTKAgg version 2.6.1

    > Is this a bug, something wrong on my system, or does it make
    > sense that the GTKAgg backend ignores everything after
    > ioff()?

All ion and ioff do is control when the drawing takes place. If "ion"
(interactive is True) then the figure should be redrawn with every
pylab command. If "ioff" (interactive is off) the figure is only
drawn with a call to savefig, draw or show. That's how it is supposed
to work -- the details are spelled out at

Let us know if you see further strangeness, and be sure to report the
output of verbose-helpful