I may be wrong here, but looking at the warning in the original post, it would seem that Gallery 2 is saying that buffering is On and it would prefer it Off, not the other way around.
I just checked the php.ini files used by DreamHost and the default configuration for output_buffering is different between PHP4 and PHP5.
output_buffering = Off;
output_buffering = 4096;[/b]
Adding something like the following to the Perl script in the wiki article should disable output_buffering in PHP5;
s/.output_buffering./output_buffering = Off/;
By the way, I was mistaken in my original reply. I have since learned that you can override some php.ini settings using ini_set within your PHP script.
This could be a lot simpler solution than copying the PHP executable and php.ini file.
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