I too cannot get my Rails app (I'm trying to run Typo CMS) running properly with Apache.
1) Everything has been chmoded correctly, even the lib/*, config/* and I even did log/* for the heck of it.
2) All my work has been done on while shelled in, not on a Windows.
3) The fcgi module is absolutely selected and my domain undoubtedly has FastCGI enabled.
4) [color=#CC6600]When I run dispatch.fcgi, I get nothing. It just sits there until I Ctrl C out of it.[/color]
[EDIT: I wasn't waiting long enough, I FCGI results in an application error and CGI results in a 404.]
5) Correct me if I'm wrong, but isn't the path to Ruby:
Note the lacking trailing slash, because ruby isn't a directory.
My app runs fine (albeit very slow) on WEBrick, but all I get is a 500 on Apache.
[color=#CC0000]To add to this, if I set up Apache to run the plain CGI instead of FastCGI (via the .htaccess file), then my app runs fine. Once I add the "f", the application fails.[/color]
If I run dispatch.cgi from the shell, I get a 404 as expected, but when I run dispatch.fcgi, I recieve an error page (only through the shell). This is the output of that error, in case somebody can make any sense of it: