[asterisk-users] error, install freePbx

[Carlos Jerónimo]

Hi, i try install FreePbx by tuturial in
http://www.voip-info.org/wiki/view/Instalaci%C3%B3n+de+Asterisk+en+Ubuntu+Server+Paso+a+Paso&view_comment_id=13443

but i have this error when i try install freepbx:

#pear install db
No releases available for package "pear.php.net/db"
Cannot initialize 'db' , invalid or missing package files
Package "db" is not valid
install failed

Why this error? help me, please.

-- 
Carlos Jerónimo