Thanks for the answer!
I am using wired connection with my iLiad. I have tested it and confirmed that it works properly. I have also checked my logon data many times and I was not able to connect to IDS.
In my IDS account the MAC address appears and disappears, that's how in the mean time I was able to download 2.10 firmware; after some time the device gives up and says that server is unreachable and I should check my network settings.
I am very sure that this is a problem with IDS and not with how I am doing it.
Right now the problem is solved anyways, because I have found the iLiadOS firmware, which is hacked on top of 2.12.1 (apparently), cracked the root password, fixed the keyboard and enjoying my device even without the developer package :-)