Why not upgrading SMP ?

[OmegaStarScream]

If you take a look at the footer , you should see this :

Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines

If you click , you will be redirected to http://www.simplemachines.org/ (the official SMP website) , what I don't understand is that I clearly see that there is releases after 1.1.19 (that we are currently using) so why not upgrading ?
I understand that the new forum software Epochtalk is under development but that doesn't explain why we are not upgrading in SMP as It could include a lot of security fixes etc... just because we didn't get hacked lately doesn't mean the forum is unhackable.

[Lutpin]

If you click , you will be redirected to http://www.simplemachines.org/ (the official SMP website) , what I don't understand is that I clearly see that there is releases after 1.1.19 (that we are currently using) so why not upgrading ?

IIRC the forum uses a heavily modified version of SMF,
and upgrading to another version would probably mean having to make all those modifications (some of which are aswell security relevant) over again.
So yes, the newer versions of SMF would bring some fixes, but so does the current version due to its customisation (which might be incompatible with newer versions of SMF).