rnfkummer() output issue

[Igor Schein <igor@txc.com>]

Hi,

? p1=rnfkummer(bnrinit(bnfinit(y^8-76*y^6+1425*y^4-5776*y^2+5776),5,1),matdiagonal([2,1]))
x^2 - 5
? \x
[&=0837e80c] POL(lg=5,CLONE):15000005  (+,varn=0):40000000  0837e834  0837e82c  0837e820  
  coef of degree 0 = [&=0837e834] INT(lg=3):02000003  (-,lgefint=3):c0000003  00000005  
  coef of degree 1 = [&=0837e82c] INT(lg=2):02000002  (0,lgefint=2):00000002  
  coef of degree 2 = [&=0837e820] INT(lg=3):02000003  (+,lgefint=3):40000003  00000001  

? p2=simplify(p1)
x^2 - 5
? \x
[&=0837eef4] POL(lg=5,CLONE):15000005  (+,varn=0):40000000  0837ef1c  0837ef14  0837ef08  
  coef of degree 0 = [&=0837ef1c] INT(lg=3):02000003  (-,lgefint=3):c0000003  00000005  
  coef of degree 1 = [&=0837ef14] INT(lg=2):02000002  (0,lgefint=2):00000002  
  coef of degree 2 = [&=0837ef08] INT(lg=3):02000003  (+,lgefint=3):40000003  00000001  

? nfdisc(p1)
  ***   polynomial not in Z[X] in nfbasis.
? nfdisc(p2)
5

It's confusing that even though rnfkummer() appears to return an
absolute polynomial, it in fact isn't, at least internally.  

Thanks

Igor