Quicktime & Subtitles: get Perian!
What I was not aware of... I installed Perian some time ago, and it sat in my System Preferences, quietly doing its job. So, all of the behaviour described in the previous post apply only if you have Perian installed. Thanx to caillou for the hint.
Nevertheless MicroDVD (.sub) formatted subtitles will not work in Quicktime even if it's QT on Perian.
Perian is a great tool every Mac user should install. It doesn't change the way Quicktime looks, behaves, no warnings, no hassle with updates, completely transparent. But it allows you to watch a number of formats which are not supported by QT out of the box.
Summary: no troubles, only benefits - get it!



