In reply to:
you can use a .htaccess file on your folder:
AddHandler application/x-httpd-php .php
php_value post_max_size 150M
php_value upload_max_filesize 150M
php_value memory_limit 250M
Well, that *seems* to "work", but you probably won't like the results! 
1) That handler invokes the mod_php installation that *may* be available on your particular server (and may *NOT* be available on *all* servers)
2) It uses mod_php 4.4.8, which can be a problem if you are expecting to be running PHP5 (and some applications *require* PHP5 )
3) mod-php runs as the dhapache user, not *your* user as is normal when running PHP-CGI under suexec, and this can cause major permissions issues with web applications that were installed using permissions appropriate for running under suexec . You will have to open up your permissions for the application to write to your directories - generally *not* a good thing to do.
4) DreamHost may, at any time, remove the ability to run mod_php. It has been "undocumented" and not advertised as a "feature" for a long time now.
In short, this is *not* a good way to attempt to modify your PHP settings for production environments. 
--rlparker