I'm using the API to create an action, which works on a different system, but on our production system, it results in an SQL error when trying to insert a row in the opmessage_usr table,

When manually executing, the error is this:

ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`zabbix`.`opmessage_usr`, CONSTRAINT `c_opmessage_usr_1` FOREIGN KEY (`operationid`) REFERENCES `operations` (`operationid`) ON DELETE CASCADE)

This regards an instance where once an extra node was present, but deactivated, and has since been migrated to 2.4

The complete API request + response can be found here:

http://hastebin.com/umivozonud.tex