At times users encounter a error while trying to configure Mingle to work with a Postgres, the error being " Ident authentication failed for user "mingle" "

This is not a problem with Mingle but with the auth_method specified in the hba.conf file of Postgres. Please read the following link to understand more about auth_method and which option would work for your setup :

http://www.postgresql.org/docs/8.4/interactive/auth-pg-hba-conf.html