Possible Duplicate:
What is TxIn’s sequence?

What are the logical conditions that would require me to change a sequence number?

Suppose there is this transaction

  txid: abcdefghi...  sequence:1  input:1someVanityName  output:1otherVanityName  ...

... and the people who mutually created this TX decide to revise some information. Perhaps change the amount, or lock duration. Since a tx number will change once the sequence # changes, (or any change for that matter) when should I logically change the sequence number?

• ...when I change the amount or lock duration?

• ...when I change the output script?

• ...when I add / remove addresses from the input portion of the tx?

• ...when I add / remove addresses from the output portion of the tx?

Eventually I may modify the transaction in such a way it has no resemblance to the original tx... and may apply to a whole different set of circumstances.

When should I increment the sequence number versus creating a new tx?