Unable to insert new Camel Case Link via the wiki markup dialog after updating the General Configuration panel.
Despite that there's no option to enable/disable camel case linking in Confluence 4.0, any update made to the General Configuration will automatically disable camel case even if it was enabled prior to the upgrade.
Enable the function from the database by making sure that allowCamelCase is true like below
If you see that
allowCamelCase is false, change it to true and restart Confluence.