If you create a settlement rule MANUALLY (within CJ20N), it's your task
to enter most char values on the profitability segment screen (because
it's user's responsibility to take care of the char values in case of a
manually created settlement rule) - only very few char values are auto-
matically filled by the system.
CJB2 works in a different way: an AUTOMATICALLY created settlement rule
contains the COMMON data of all SD documents that refer to the WBS ele-
ment for which CJB2 was executed - especially the sales order number if
there is only one sales order involved.
Please also refer to SAP note 332909.