[NTG-context] does expandaparameters work

Hello, I use "\expandparameters" in a macro definition. -- \expandparameters\setupbackgrounds[page][background={\currentvalue,#1}] -- This works in MkII (texexec), but doesn't work in MkIV (context). If I define all layers in a single declaration, the results with MkII and MkIV are identical. Should this work? Or do I have to add something for MkIV? Thanks and kind regards Erik