Strange problem with "integrate" : "Convergence problem..." error 24 (Scilab 4.1.2)

[Remi G.]

Hello!

I'm facing a strange problem with the function "integrate" (and also 
with "intg") with Scilab 4.1.2 :

If I want to integrate x^5 between -%pi and %pi, it works (hopefully) :
  integrate('t^5','t',-%pi,%pi)

But if replace 5 by a variable k (that I've defined before of course) it 
will not work for k>=5!
  i=5
  integrate('t^i','t',-%pi,%pi)

Here is the error message I get :
    !--error 24
  convergence problem...
  At line      26 of function integrate called by :
  integrate('t^i','t',-%pi,%pi)

That's really annoying because I can't code my least square 
approximation procedure which is... for tomorrow!
If someone could give me a way to go through this issue!
Thank you very much!

Rémi.