How to add projects to locked "Original story points" ?

[Renni Verho]

We have project which would like to change from time estimations to story points. 

Original Story points is by some reason locked for one earlier project and I did not manage to add this new project tried many ways eg. via custom_field settings (/secure/admin/ConfigureCustomField!default.jspa?customFieldId=16212) .

Any ideas how I could get more projects to use Original story points custom_field ? 

Field is possible to fill in portfolio side and commit changes, but.... column is still empty after commit.