Reverting to an old version in a branch

The package "gnome-shell-extension-weather" is currently in the f-16, f-17 and f-18 branches. compatibility with Fedora 16 (please see this bug report: https://bugzilla.rpmfusion.org/show_bug.cgi?id=2564 ). Is it possible to revert the package to an old build (the last compatible with F16) in the f-16 branch and then make such branch (and only that) stick to that version in the future? If so, how to do that? Thank you in advance. M.M. (odysseus)