PEAR package installation silently fails

Distribution: Ubuntu 9.10 Karmic
Binary package hint: php-pear

So, I have an php-pear package installed (aptitude install php-pear)

Ok, let's install any package —
$ sudo pear -vvv i XML_RPC2
[sudo] password for andy:

Notice: file_exists(): Unable to find the wrapper "channel" - did you forget to enable it when you configured PHP? in PEAR/Downloader/Package.php on line 1517

Notice: is_file(): Unable to find the wrapper "channel" - did you forget to enable it when you configured PHP? in PEAR/Downloader/Package.php on line 1527

Notice: is_file(): Unable to find the wrapper "channel" - did you forget to enable it when you configured PHP? in PEAR/Downloader/Package.php on line 1527
pear/XML_RPC2: Skipping required dependency "pear/PEAR" version 1.9.0, already installed as version 1.9.0
pear/Cache_Lite: Skipping required dependency "pear/PEAR" version 1.9.0, already installed as version 1.9.0
Downloading "http://pear.php.net/get/XML_RPC2-1.0.5.tgz"
downloading XML_RPC2-1.0.5.tgz ...
Starting to download XML_RPC2-1.0.5.tgz (49,522 bytes)
.............done: 49,522 bytes

Warning: unlink(/tmp/glibctestW0pWtJ): No such file or directory in System.php on line 206

…and package appears not installed.

As far as I have tested it, only package installation fails at the moment.