Asset Book restriction in the invoice distribution form

Hi,
We have multiple assets books, one for each operating unit.

While creating asset invoices,asset book has to be attached at the Invoice distribution.
Instead of seeing the asset book relevant to the OU, we are able to see and attach asset book of other OU.

I hope this is a generic issue and seems there is no standard solution for this.

Can anyone please let me know if they have  come across such problem and how it was handled.

Thanks in Advance
Amar