[Zope] zope backward compatibility policy?

[gabor]

hi,

what's the backward compatibility policy of zope?

i'm asking because while upgrading from 2.6.4 to 2.7.2 we had some
problems. simple ones (like the 'lines' property type seems to have 
changed from list to tuple), but still problems.


i checked the changelogs, and this change does not seem to be mentioned.

i thought that if someone is not in the changelog, then is supposed to 
be unchanged.

or not?


p.s: i am still a beginner in the zope world, so maybe i am completely 
wrong :)

gabor