radical command does not work over C

For some reason the command "radical(I);" does not work for the polynomials with complex coefficients but works when the coefficients are rational. Can anything be done about it?

radical does not work over "inexact" fields (like complex or real) because
no factorization over such fields is implemented.
Use the algebraic extension of Q by i with i2+1=0
(ring r=(0,i),....;
minpoly=i^2+1;)