Instead of updating all the fields, it might be easier to create symbolic links for everything, e.g.
/download/punbb-latest-stable.tar.bz2 will be a symbolic link to
/download/punbb-1.2.10.tar.bz2
And then you'd only need to change the version information.

It'd be nice if the freshmeat.net project page would be kept up to date when new releases come out.
http://freshmeat.net/projects/punbb/
Thanks