On public servers, wich I'm dealing with, I can only find one good solution. You should run the script setuid to some user, and let the script then read a datafile with the passord in it. Make sure that user is the only one able to read the password file. Now the location doesn't need to be secure cause the webserver itself or any other user can't read the file. Suggestions welcome for other ways of dealing with this.
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Berik