I have read the wiki, and I successful compiled custom PHP.
However, I have try to compile eaccelerator, I encounter some problem.
The first is compiling requirements is not match. Our server don't install such as AutoConf ,AutoMake, and M4.
The second is eaccelerator should run under mod_php ( as I know, I don't know whether this is right:( ).
So, try to compile it by ourself is Mission Impossible for me.
And, I have requested dreamhost to support it, the support suggest we should sumit a suggestion on https://panel.dreamhost.com/index.cgi?tree=home.sugg& .
search eaccelerator, and vote that!
Wish dreamhost will install eaccelerator.
And, you can visit http://blog.robinz.info/archives/2006/02/11/performance-wp-cache-vs-eaccelerator-enable-mod_rewrite-for-apache-is-a-good-choice/ to know how the performance is using eaccelerator or wp-cache