Cant process ABUMN in the current year

I wish to transfer an Asset from one Asset class to another in January 2012. The Asset value date is in a closed FY (2011) and this is not allowing me to post. But, if I try it using asset number from the year before (2010,2009,2008,..), it works..

I wonder what is the reason it's not working with year 2011..?

And how can i handle this and ensure that the Asset from 2011 is transfered to the new Asset class..

Please help me. Thanks before

Ocep00