I don't really understand this closed source thing in old, non-active software. I mean what would any company will lose, if they release a couple lines of code. Is it really that important. I think only thing that will change is the open source community's respect to that company.

There's ID Software, a pure software company which gain their revenue mostly from the engine sales. And they released every single one of their engine's source in GPL license except the one they're actively developing that time. And because of that, we can play ID's games in many platforms(including N900). They'll release IDTech4's(Doom3 engine) license this year too. I guess we will see a Doom 3 port in N900 too after that.