I just released PEAR-1.4.10 (Greg released it again later, I forgot to commit the new state, stable
). Besides many bug fixes, this release boosts support for open_basedir and safemode.
It is finally possible to run the installer in an open_basedir environment without dozens of error messages. Part of the solution was to add two more configuration options:
- temp directory (temp_dir)
- download directory (download_dir)
They respectively allow you to define a custom temporary file directory and another for the downloads. Until now the system temp directory was used, and many ISP forget to add it to the open_basedir list. I think these two options will spare many headaches for some of our users 
Also, I really hope it is the last 1.4.x release, we will now focus on PEAR 1.5.x and up but more about that later this week.