how can I post the comment into LP from rest api?

Posted on behalf of a customer. Original posting date 2014-11-21.

Hi support,

I have the documentation, according to that when i will post the request for a comment than i need following json

{
"comment": "Working on it...", 
"id": 11111, 
"type": "Comment", 
"item_id: "77777", 
...

1 doubt) according to me field "id" is comment id and "item_id" is task id, isn't it ?
2 doubt) If field "id" is the comment id then how can i post the new comment for task because for new task there is no any comment id.
3 doubt) For new comment for a task what value me should put into the Json ?
3 doubt) In my live server the task ids are 8 digits but in LP api documentation examples item_id is 5 digits, is it the cause of error 400
bad request ?
4 doubt) can i post the created OR updated date value within this comment for a task ?

i want to know what is the value of "id" field ? is that "id" the comment id ? it is comment id then please let me know without create a comment how can i get the comment id, that is not possible.