3DES key generation

[Egon Andersen]

David Shaw wrote:
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> Hash: SHA1
> 
> On Thu, Apr 17, 2003 at 05:13:41PM +0200, Egon Andersen wrote:
> 
>>Hi,
>>
>>I know that gpg can use 3DES cipher algorithm, but how do I generate the 
>> 128-bit key used for this?
>>
>>I can see that gpg can generate DSA and ElGamal, but I can find out how 
>>to generate keys for 3DES.
> 
> 
> GnuPG uses 3DES for session keys, so you do not need to generate
> them.  They are generated automatically as needed.
> 

Well, this true when I use gpg in both ends.
But my problem is that the opposite end only uses symmetric ciphers and 
I have to inform them about my 3DES key for this session (encrypted with 
another 3DES key).
So therefore I need to generate 3DES keys, encrypt it with a given 3DES 
key, at send it to the receiver.
(I haven't 'invented' this system, the receiver did.)

So is there any way I can generate/get 3DES key?
Perhaps using some library?

Best regards
Egon Andersen