Upgrading PEAR

[youds]

Hi

I'm trying to upgrade PEAR from 1.9.0 to 1.9.1 and keep getting the following message:

upgrade ok: channel://pear.php.net/Archive_Tar-1.3.7
upgrade ok: channel://pear.php.net/Structures_Graph-1.0.3
upgrade ok: channel://pear.php.net/PEAR-1.9.1

Warning: require_once(PEAR/ErrorStack.php): failed to open stream: No such file or directory in PEAR/PackageFile/v2.php on line 19
PHP Warning:  require_once(PEAR/ErrorStack.php): failed to open stream: No such file or directory in /usr/local/lib/php/PEAR/PEAR/PackageFile/v2.php on line 19

Warning: require_once(PEAR/ErrorStack.php): failed to open stream: No such file or directory in /usr/local/lib/php/PEAR/PEAR/PackageFile/v2.php on line 19
PHP Fatal error:  require_once(): Failed opening required 'PEAR/ErrorStack.php' (include_path='/usr/local/lib/php') in /usr/local/lib/php/PEAR/PEAR/PackageFile/v2.php on line 19

Fatal error: require_once(): Failed opening required 'PEAR/ErrorStack.php' (include_path='/usr/local/lib/php') in /usr/local/lib/php/PEAR/PEAR/PackageFile/v2.php on line 19

This is from the default PEAR installed by custombuild.