Flickering movies

[Marco Caliari]

Dear maintainers,

I'm not sure I will describe a bug or just a different behavior, so I'm 
writing to the maintainers' list.
The execution of the following code in Octave 3.0.5

x = linspace(-1,1);
for i = 1:50
  plot(x,i*x.^2)
  axis([-1,1,0,50])
  pause(0.1)
end

produces a nice and fluent "movie". In particular, the axis box seems 
fixed (it is fixed to my eyes), and only the curve inside moves. With 
3.2.0, I get a very flickering movie, with the axis box clearly redrawn 
at each step. What is strange, moreover, is that if I change

pause(0.1)

with

pause(0.01)

the axis box changes its dimensions during the loop and so the illusion of 
a movie disappears. I'm using gnuplot 4.2.5.

Best regards,

Marco