Equation Display or Problem

[Thomas D. Dean]

Back to my previous problem.  I expected to bet the same system from 
either the zpk or equation representation.  But, they are different

octave:1869> clear all
octave:1870> a0 = 1e5;
octave:1871> w1 = 1e4;
octave:1872> w2 = 1e6;
octave:1873> s = tf('s');
octave:1874> a_eqn = a0/(1+s/w1)/(1+s/w2)

Transfer function 'a_eqn' from input 'u1' to output ...
                1e+05
 y1:  --------------------------
      1e-10 s^2 + 0.000101 s + 1
Continuous-time model.

octave:1875> a_zpk = zpk([],[w1,w2],a0)

Transfer function 'a_zpk' from input 'u1' to output ...
               1e+05
 y1:  ------------------------
      s^2 - 1.01e+06 s + 1e+10
Continuous-time model.

octave:1876> a_eqn(w1)
ans =  4.9495e+04 - 5.0495e+04i
octave:1877> a_zpk(w1)
ans =  4.9495e-06 + 5.0495e-06i

Is this correct?  What am I doing wrong?

Tom Dean