How to change the label of invoice vendor in ax 2012 ?

Hello,

I'm trying to change the label of invoice vendor ( the field  txt of table transactTxt) , by default is equal to

 ' VendorGroup'  N°Invoice 'AccountVendor' , i made some change in this Class purchinvoicejournalPost>>TransactionTxt(LedgerTransTxt  _ledgerTransTxt) , but no result !! 

can someone help me , Thanks.

Taoufiq

Thanks