I want to buy Linux version

[aniruddha]

Lol, this problem is fixed for Gentoo users. Just use the Penumbra: Overture ebuild: http://bugs.gentoo.org/show_bug.cgi?id=179733

Update:
Please post all your problems related to acceptance of the serial number here:
http://frictionalgames.com/forum/showthr...p?tid=1113