DB Model for custom-fields management

[Chris Bassett]

I'm looking to write a webapp that has a series of configurations. For each configuration, there can be any number of questions that needs to be asked. What I'm trying to do is create a generic "custom fields" table in a database that will allow the admin of the webapp to add as many custom question fields as needed. Some configurations will not need any custom question fields, whereas other may have 10 or more custom question fields associated with it.

In the end, I also need to be able to go through and determine which custom questions meet or fail a certain set of requirements.

Any ideas on how I could implement something like this?