You don't quite get it. They rolled their own because it was faster and more efficient for *their* purposes and made it easier to use on different platforms, including those with just a few MB to run in.
And it wasn't very insightful to worry about whether people care about EPOC anymore. The point was that a web browser was made for a platform with limited resources (Psions) that used a third party 'one size fits all' JPEG library and it was not a pleasant experience for its users. The same thing applies today for mobile phones - which are important to Opera, along with the requirement for the same code to run on all platforms.
Thanks for picking up on my typing by the way. It's important we focus on such things when talking about JPEG libraries.
The simple fact is that Opera wrote some new software and it has some bugs in it. Wow, most people write perfect code the first time. When was the last time you heard of any bugs in Windows, Firefox, Apache, MySQL or PHP? Yeeees.
What I find strange is why so many people have a problem with some company doing whatever it likes with its product and resources. Why does it offend you? Other programs introduce new features or replace blocks of code and introduce bugs all the time, what's so special about a JPEG decoder?