Apache 2.2 + mod_fcgid + suexec?

Is anyone successfully running a rails app on Apache 2.2 with
mod_fcgid and suexec? If I remove the SuexecUserGroup
directive from my Apache config file my app works fine. If I
leave it in I get the following [abbreviated for relevance]:

mod_fcgid: process …/dispatch.fcgi(11418) exit(communication error),
terminated by calling exit(), return code: 255

FWIW with SuexecUserGroup set I can run other scripts (Ruby
and otherwise) just fine and with the correct user:group.

I realize this is FAQ material but I’ve googled, scoured the
Rails wiki, … and I am still coming up shorthanded. Any insight
would be greatly appreciated.