Could be because you have precondition on yout N900 that testers didn't have. Also if something crashes on your N900 it doesnät meant that it happens on all the other people also. So it´s after that happens in future search bugzilla, search forums and report and see if there is other people with that issue also.

BUT what I believe is that after long and tedious app testing to extras Nokia released PR 1.2 that broke some apps in extras (which is considered as safe also by nokia because they have enabled it out of box n900). They should have released developement fw so that some of porblems with extras stuff could have been spotted.