date in salesinvoiceline and custledge entry not same why

ahmedba

Hi guys Now i have one problem i make order then invoiced it.after i invoiced i found this order display in sales invoice header

in order date and posting date with 6/01/2013 and in sales invoice line with another date 30/12/12

now i need date found in sales invoice header same date 30/12/12 (meaning sales invoice header and sales invoice line) have date 30/12/12 and also i need to change it in custledger entry table from 6/01/13 to 30/12/12 how i change