Does anyone know how to use pear to set the system path to pear.conf?

Syntax: pear config-set Filename /etc/pear.conf

Getting an error (config-set (Filename, /etc/pear.conf, user) failed, channel

I am trying to set to some other places (not /etc/pear.conf), but I am just using /etc/pear.conf as an example
I am able to set other params,,, just not this one ~~