PROGRESS --- so simple
Great, thanks, I installed and used strace.
A lot of ununderstandable things came out but,
I saw somewhere in the output "network is unreachable".
I switched the connection from wifi to gprs and it worked, a lock came in seconds.
Though the ADSL modem firewall is inactive, it is not working via wifi nor usb networking.
Any clue of the reason? (all prior tests with wifi were done in "phone mode" but without gprs internet connection)

WIKI
So now, I can add some infos to the wiki. I guess I shouldn't delete or add into your text but below it with an "edit:". Am I right?
Also, how can I login to the wiki. Seems not to be the same account than here. (searched on different places in maemo.org but found nothing about that).