Should I be able to enter search criteria in DFF segments?

Hello,

I am using R12 'oldstyle' Oracle Forms.

We setup a context sensitive DFF on PO Headers.

On PO Headers Summary form I press F11 (Query Enter) and would exect to be able to enter search criteria into the DFF segments. But the whole DFF is grey, no input possible.

Can please somebody tell me if this is standard behaviour? What can I do to be able to query for values in the DFF as well?

Thank you!