Greg Beaver and crew have announced the release of PEAR_RemoteInstaller, version 0.3.0 today. The package makes possible the synchronization of PEAR installs between machines without the need for shell access.
This version is essentially a bugfix release, as the initial versions did not in fact work with PEAR version 1.4.3 or newer (I no longer had a remote host that supports unencrypted ftp access with which to test it). Although it adds ftps and sftp support, it does not change anything about the implementation of the underlying code, or the commands. Future versions will be far more user-friendly and well-thought out.
This new version requires that you use PHP 5.1 or higher to make it work (it needs the ftp streams to grab needed files). You can grab this latest version directly from its page on the PEAR website.