In case of a restart, v[0] and v[1] were incorrectly initialised.
This was interpreted by ssl3_get_client_key_exchange as an RSA decryption
failure (don't ask me why) and caused it to create a _random_ master key
instead (even weirder), which obviously led to incorrect input to
ssl3_generate_master_secret and thus caused "block cipher pad is
wrong" error messages from ssl3_enc for the client's Finished message.
Arrgh.