I can't download Smantha's voice

Hello, today i was trying to download the Samantha's voice, because it is close to siri 😉

However, when i select to download the voice from Speech in System Preferences, it says this error:

The voice "Samantha" can’t be installed now because you are not connected to the Internet.

Buy I AM connected to the internet, by an ethernet cable. What's happening? Can this be solved? Thank you very much.

PS: I am using an imac from 2009 and OSX Lion 10.7.4