unified versions?

[Tommaso Teofili]

Hi all,
I'm wondering if it'd be better / required to have all the modules set to
the same version.
We have the parent POM to 0.2(-incubating-SNAPSHOT) but lots of other
modules have 0.1 / 1.6 / 0.12 and so on.
What do you think about it?
Tommaso