One more possibility. Have the form post by e-mail. Then have a perl script read the mail box every so often and write the text file. No CGI that way but you'll need the root user/Administrator to set up a cron/scheduled job to run the perl script every so often.

And, of course, if you had a helpful root/admin you wouldn't have this problem in the first place. =) But I wanted to point out your problem is solvable with perl and some ingenuity!

--
$you = new YOU;
honk() if $you->love(perl)