Pear Installer Config Question

Hi, I know this has been on the list before; sorry but I'm having trouble tracking down the info. How can I setup the existing pear installer so that I can have another pear installation on the same machine? I don't actually want to reinstall the pear installer, I just want to configure the existing one so that it points to another location without messing up the currently installed pear src tree. I thought I might just write a wrapper script with all the options in there, but I'm not sure which options I should specify and which I should leave alone. Example: #!/bin/sh pear -v \ -d foo=bar \ -d php_dir=/web/lib/php \ and so on... Any advice, pointers to some documentation on this, or other posts would be much appreciated. Many Thanks, Matt.