The online documentary also says this
http://help.sap.com/saphelp_46c/helpdata...88b/content.htmSame document number in MM and FI document
Use
As of Release 4.6C, you can now assign identical document numbers for a business transaction for Logistics Invoice Verification in the Materials Management and Financial Accounting components. If you set external number assignment for the number ranges of the Financial Accounting document types, the number of the Materials Management document is transferred to the leading Financial Accounting document.
In contrast to Financial Accounting, the number range interval for the documents in Materials Management is company code-independent. This leads to the following restrictions when using external number assignment:
For each company code used in Materials Management for which external number assignment is set, the same number range interval must be set in Financial Accounting; this also applies to cross-company code transactions.
Uninterrupted number assignment for financial accounting documents is not guaranteed.
The document types used for revaluation, invoice reduction, and additional documents must use internal number assignment.
In previous releases, external number assignment was not possible in Financial Accounting, so identical document numbers could not be assigned.
Effects on Customizing
To work with the same number assignment in Materials Management and Financial Accounting, maintain the activity Maintain Document Types and Number Ranges in the Logistics Invoice Verification section of the Implementation Guide (IMG).
With best regards
Jens Plucinski
www.jensplucinski.deConsultant Business Administrator SAP FI