Who do you want to hide the message from ? parents? previous (or current) partner? feds?
Depending on IT knowledge of your opponent and the authority they have over you, nothing may be secure.
if they have physical access to your computer or can get it – whether its that “ex you stayed friends with” visiting you and going through your PC files when you are asleep, or 5 armed feds putting your door off the hinges, even if you use hard encryption the fact you suddenly used it or installed it would be a clue irrespective of whether your opponent can actually decode the message.
A bit like walking down the high street in summer whilst wearing a balaclava or other mask, it attracts suspicion. Even if its not feds this sort of thing can destroy a family relationship or friendship through lack of trust.
that said though it might seem old fashioned and if you are talking about large amounts of drugs then caution is advised, its harder than folk think to monitor the voice traffic of an old fashioned telephone. Although in some cases the techie bit is trivial (like if you were a big dealer and feds had already got a warrant to monitor you), in cultural and legal terms there still seems to be more of a expectation of privacy on a voice telephone (especially mobile) than on high tech internet communication (consider how even gutter press journalists are actually being nicked for hacking into phones when they are allowed to get away with all sorts of other surveillance).
However after nearly 20 years of working as a IT/telecoms engineer, and dealing with security of communications, if at all possible I try and avoid getting myself into this situation.
I don’t even do illegal drugs any more these days but when I did and this awkward situation was unavoidable, I’d use a normal phone to arrange a face to face meeting with someone I trusted. Even then I was wary over what I said on the telecommunications network.
I have never arranged to send drugs across national borders so have no knowledge of comsec associated with this and would suggest that if you must do it you weigh up the risks and rewards and be prepared for any comeback/penalties. it seems to be only a caution these days or even just losing your money and a letter from UKBA for small amounts for personal use, so maybe the best advise there is “don’t be overly paranoid but don’t be greedy either…”
