I'm not overly hopeful about this either, but I'm thinking if it's considered a critical update by Adobe, and Nokia are still obligated to supporting the N900 then there is an outside chance, especially given the fact that they recently gave a small update regarding the security certificates.

Anyway, I have raised a bug, https://bugs.maemo.org/show_bug.cgi?id=12437 and emailed security@maemo.org as per Andre Klapper's suggestion.

I'm not holding my breath... lol