I made this commit for 1.3 only (at this moment). (Details: https://sourceforge.net/p/ledger-smb/code/5993/ )
Here is the demo video: http://youtu.be/H1gWFM-_wVc
It contains additional field on AR/AP transactions, called Invoice created.
In the following cases this field is readonly:
Basically this field for record the creation date for all invoices made by ledgersmb itself, this is why the field is readonly in the previous cases.
Please note, even the database also extended to contain this field, the code to join the database to the UI and vice versa does not exist yet.
This commit also contains a change: In the Defaults the invoice number is readonly to avoid alter the series. In general case it should enough. Variable part of the invoice number, like including the year, maybe possible with <?lsmb ?> syntax. Need check.
Please comment it.