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If it's not running for you even PEAR installed try to make an upgrade of PEAR (pear upgrade PEAR).
If you are using a Debian sarge system (currently the stable release) with php4-pear installed, you will still not have a pecl command.
The fix to this is to upgrade pear.
Unfortunately, pear upgrade PEAR will also error out stating that you need pear-1.3.3 minimum.
The fix to this is to specify the version of pear that you want to install. In case it wasn't obvious, that means you want to
pear upgrade PEAR-1.3.3
pear upgrade-all
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