Lorna Mitchell's Blog: Downgrading a PECL Module
Most of the time you spend using PECL modules, you'll either be upgrading or installing new ones. Occasionally, though, you might need to move the other direction and roll back to a previous version. This handy tip from Lorna Mitchell shows you the handy single-command method.
Recently I saw some weirdness in an existing application when I upgraded a PECL module that the application depended on. To figure out if that really was the problem, I wanted to downgrade the module to its previous version. There is no opposite command to "upgrade" but you can instruct pecl to install a specific version of a module, using the -f switch to force pecl to overwrite newer modules.
In her case, she needed to downgrade the pecl_oauth package to 1.0.0 from 1.1.0. The trick lies in the "-f" switch for the "pecl install" allowing you to specify the version to install.