Posting a Sales Invoice, I want a G/L Entry Desc. per line

Hi all,

When posting a sales invoice, on "G/L Entry" table, in Description field, I want a specific description for every line (Let's say that I want to put the "G/L account" name).

NAV Standard : (The same description for all lines of the invoice in G/L Entry table)
Document No. G/L Acc No. Description Entry No.
Invoice08/01 707900 Order 1001 2754
Invoice08/01 709000 Order 1001 2755
Invoice08/01 411900 Order 1001 2756

What I want : (Every line take the G/L Account name)
Document No. G/L Acc No. Description Entry No.
Invoice08/01 707900 Desc1 2754
Invoice08/01 709000 Desc2 2755
Invoice08/01 411900 Desc3 2756

With in Table 15 G/L Account :
Desc1 : Value of field Name for the account 707900
Desc2 : Value of field Name for the account 709000
Desc3 : Value of field Name for the account 411900

How to make this modification on the process of posting, I CU 80 ? How ?.

Thanks.