Hi again.

I tested this with some other ciphers, also deliberately forcing a
specific cipher. When testing with the openssl s_server command,
Diffie-Hellman parameters are generated.

According to [1]  in the NOTES section, there are some conditions for
specific ciphers. If these conditions are not met, it could cause a "no
shared cipher" error to be produced. It seems that this might be a
problem since I don't explicitly supply Diffie-Hellman parameters and I
don't know if the are generated on the fly by openssl, but I suspect
this to be not the case since this can take quite a while depending on
their length.

Greetings,
André

[1] http://www.openssl.org/docs/ssl/SSL_CTX_set_cipher_list.html