encoding of Gmp.mpz objects does not work.
Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=4257
Reported by Martin Nilsson, IDA nilsson@pike.ida.liu.se
> encode_value( Gmp.mpz(3) );
Cannot find Gmp.mpz(3) in Gmp.
/usr/local/pike/7.6.91/lib/master.pike:3761:
master()->find_index(Gmp,Gmp.mpz(3),UNDEFINED)
/usr/local/pike/7.6.91/lib/master.pike:3954:
master()->nameof(@0=Gmp.mpz(3),UNDEFINED)
HilfeInput:1: HilfeInput()->___HilfeWrapper()