Dissociating a non-existant floating ip from a server throws a 500 instead of a 404

Description

remove floating ip 0.0.0.0 from a server results in Compute Fault 500 Instead of 404:

curl -D - -X POST -H 'x-auth-token: <TOKEN>' -H 'x-auth-project-id: CloudTester1' -H 'user-agent: Tester' -H 'accept: application/json' -H 'content-type: application/json' <Endpoint>/v2/YWhkdHXqeGwU6UNE8juB-PLe/servers/06c7d848-a052-49a0-8476-faa4746a121a/action -d '{"removeFloatingIp": {"address": "0.0.0.0"}}'
HTTP/1.1 500 Internal Server Error
Content-Length: 128
Content-Type: application/json; charset=UTF-8
X-Compute-Request-Id: req-8825d292-cd9e-492d-9745-287781d12ca9
Date: Tue, 02 Oct 2012 17:50:24 GMT

{"computeFault": {"message": "The server has either erred or is incapable of performing the requested operation.", "code": 500}