Since i'm not getting any response in the official support forum for FIELD EDITOR I decided to repeat the question over here in the hope someone out there knows how to solve this.
Since i started development on a ee 2.8.1 system i’m getting a "Unable to load the requested class: services_json" error when i try to save changes to my custom field group using FIELD EDITOR.
Googling the error helped me find a similar error in the Zoo Flex Admin add-on but the solutions posted there didn't help me fix this issue. http://devot-ee.com/add-ons/support/zoo-flexible-admin/viewthread/12713
Do you have any clue how to fix this?