Outgoing Payment in SBO 2004 C

Hello!

I have problem with pay for purchase invoice in SBO 2004.

Document: Outgoing payments

Serwer/System date: 07.01.2009

Purchase Invoice from day: 19.12.2008

Posting period: 12_2008

Total paymant: 5054,94

If I will try pay for this invoice where posting date and tax date is set on 19/12/2008, in SAP appears two messeges.

first:

A previous document of this type has been created with a later date

second:

Amount paid does not match amound to be paid at 5054,94 Transfer this difference to new posting?

If I try change serwer date on 31/12/2008 and restart SAP, paymanting operation end successfull.

How I can make this payment without changing serwer date?

Thanks,

Krzysztof Sala