posting date in CO11N

Hi gurus,

Hope you all are doing well!

My query is:

I am creating a production order on monthly basis. Start date for example. is 01.10.2010 and finish date is 31.10.2010.

I am confirming daily production by entering posting date in CO11N.

If I try to confirm this order in CO11N on 1st Nov by giving posting date as 01.11.2010, system should give me a error message that it is October month production order and hence my confirmation should not be allowed.

How this can be achieved? kindly help.

Regards.