     x = new SHA1()
     x.feed(@_s.toArray())
     x.feed(auth.digest)
-    @_x = BigNum.fromArray(x.digest) #, 20)
+    @_x = BigNum.fromArray(x.digest)
 
     # Password verifier
     # v = g ^ x mod N

    # M2 = H( A | M1 | K )
    @_M2 = new SHA1()
    @_M2.feed(@_A.toArray())
    @_M2.feed(@_M1.digest) #, 0, _M1.digestLength)
    @_M2.feed(@_K)
    @_M2.finalize()


    u = new SHA1()
    u.feed(@_A.toArray())
    u.feed(@_B.toArray())
    @_u = BigNum.fromArray(u.digest)

    # Client-side session key
    # S = (B - (kg^x)) ^ (a + ux)
