Logging in to the phone using telnet to find this out is not useful in real life scenarios. trust me, you do not want to login (using telnet) to your users' phones over the internet just to find out if he got back a 416 or a 404.
It is also not very secure to use telnet for remote connections.
Reporting of actual (XXX) error code could be an option, but should be configurable.
"Reorder" is bad. it tells the user to actually try again, which will not help most of the time since an error occurred that will not be resolved by itself.
| Error Code | Today | Wanted |
| 100 Trying | "Proceeding (in 100)" | "Trying (100)" |
| 180 Ringing | "Ringing Destination (in 180)" | "Ringing (180)" |
| 181 Call Is Being Forwarded | "Proceeding (in 100)" | "Call Is Being Forwarded (181)" |
| 182 Queued | "Proceeding (in 100)" | "Queued (182)" |
| 183 Session Progress | - | "Session Progress (183)" |
| 200 OK | N/A | N/A> |
| 300 Multiple Choices | "Reorder" | "Error (300)" (not implemented) |
| 301 Moved Permanently | "Reorder" | "Error (301)" (not implemented) |
| 302 Moved Temporarily | "Reorder" | "Error (302)" (not implemented) |
| 305 Use Proxy | "Reorder" | "Error (305)" (not implemented) |
| 380 Alternative Service | ?broken? | |
| 400 Bad Request | "Reorder" | "Bad Request (400)" |
| 401 Unauthorized | "Reorder" | "Unauthorized (401)" |
| 402 Payment Required | "Reorder" | "Payment Required (402)" |
| 403 Forbidden | "Reorder" | "Forbidden (403)" |
| 404 Not Found | "Reorder" | "Not Found (404)" |
| 405 Method Not Allowed | "Reorder" | "Method Not Allowed (405)" |
| 406 Not Acceptable | "Reorder" | "Not Acceptable (406)" |
| 407 Proxy Authentication Required | "Reorder" | "Authentication Failed (407)" |
| 408 Request Timeout | "Reorder" | "Call Timeout (408)" |
| 410 Gone | "Reorder" | "Not Found (410)" |
| 413 Request Entity Too Large | "Reorder" | "Request Entity Too Large (413)" |
| 414 Request-URI Too Long | "Reorder" | "Request-URI Too Long (414)" |
| 415 Unsupported Media Type | "Reorder" | "Unsupported Media Type (415)" |
| 416 Unsupported URI Scheme | "Reorder" | "Unsupported URI Scheme (416)" |
| 420 Bad Extension | "Reorder" | "Bad Extension (420)" |
| 421 Extension Required | "Reorder" | "Extension Required (421)" |
| 423 Interval Too Brief | "Reorder" | "Interval Too Brief (423)" |
| 480 Temporarily Unavailable | "Reorder" | "Temporarily Unavailable (482)" |
| 481 Call/Transaction Does Not Exist | "Reorder" | "Call/Transaction Does Not Exist (481)" |
| 482 Loop Detected | "Reorder" | "Loop Detected (482)" |
| 483 Too Many Hops | "Reorder" | "Too Many Hops (483)" |
| 484 Address Incomplete | overlap dialing. implemented? | |
| 485 Ambiguous | "Reorder" | "Ambiguous (485)" |
| 486 Busy Here | "Line Busy" + SLOW BUSY | "Line Busy (486)" + SLOW BUSY |
| 487 Request Terminated | "Reorder" | "Request Terminated (487)" |
| 488 Not Acceptable Here | "Reorder" | "Not Acceptable Here (488)" |
| 491 Request Pending | "Reorder" | "Request Pending (491)" |
| 493 Undecipherable | "Reorder" | "Undecipherable (493)" |
| 500 Server Internal Error | "Reorder" | "Server Internal Error (500)" |
| 501 Not Implemented | "Reorder" | "Not Implemented (501)" |
| 502 Bad Gateway | "Reorder" | "Bad Gateway (502)" |
| 503 Service Unavailable | "Reorder" | "Service Unavailable (503)" |
| 504 Server Time-out | "Reorder" | "Server Time-out (504)" |
| 505 Version Not Supported | "Reorder" | "Version Not Supported (505)" |
| 513 Message Too Large | "Reorder" | "Message To Large (513)" |
| 600 Busy Everywhere | "Reorder" | "Line Busy (600)" + SLOW BUSY |
| 603 Decline | "Reorder" | "Call Rejected (603)" |
| 604 Does Not Exist Anywhere | "Reorder" | "Not Found (604)" |
| 606 Not Acceptable | "Reorder" | "Not Acceptable (606)" |