I have noticed that the ini setting eaccelerator.filter doesn't work at all. I have my server configured so that it parses .html as php files but I wanted to disable caching of such files, so I have put !*.html in eaccelerator.filter. It didn't help, .html files still get cached. I have also tried to put "*.php" in the setting, so only *.php files would be cached, but still, it did not help. On the top, I have even spoted one .txt file in the cache which is not set to parse as php at all.
PHP 5.1.2, Apache 1.3.34, eAccelerator 0.9.5 beta2