How to make the Parked Document Posting date is changed to system date in SAP

Hi Experts,

While doing the parked document posting. The Document & Posting date is 01.02.2014. We got the approval today(15.04.2014). Now I am trying to post the same parked document, system taking old date only.

As per my client requirement today date only they want. What needs to be do for this requirement.

I used T.code: OBD1 - Maintained - Status is 1 (Posting date is changed to system date)

I have posted new parked document with old Document & Posting date is 01.02.2014: 

But there is no changes happing, May I know what could be the reason.

How to fulfil this requirement.

Thanks & Regards,

Vijay