Use the key supplied in the package in first post. Just extract telegram in /home/user/

So you end up with this:

/home/user/
/home/user/telegram/telegram -- The executable
/home/user/telegram/tg.pub -- The public key

Now cd to /home/user/telegram/
and run ./telegram -k ./tg.pub

it will ask for your number and sends you a SMS.
Libraries I have installed with exact name:
Libconfig8
libssl0.9.8 (No 0.9.7 installed)
libreadline4
libreadline5
libreadline-common


Good luck. Still I hope someone with enough skill will make a Maemo IM plugin

Edit: @above, why you run telegram as root?