asksign and integrate



I cant really understand why assume doesnt work as it should to.

Why maxima still asks the question, even though I did answer it with 
assume()??

     (%i23) assume( (y-1)*(y+1) > 0 )$ integrate(log(x^2+y^2),x,0,1);
     Is  (y-1)*(y+1)  positive, negative, or zero?


But if I ask directly asksign() with this kind of assume it does work:

     (%i27) assume( (y-1)*(y+1) > 0 )$asksign( (y-1)*(y+1) );
     (%o27) pos


I suspect it has smth with re-ordering of expression inside maxima 
before it outputs it, because:

     (%i4) -1+y;
     (%o4)                                y - 1

I assume asksign() does this kind of reorder before outputting the 
question as well, while internally has different representation of the 
expression.

My question is: can I turn off this reorder somehow so asksign() will 
write their questions properly, so I can use output of its question in 
assume() then.

Thnx,
Alex