Adding Additional Parameters on Selection-Screen of VL06F

Hi Gurus,

I am having a requirement of adding two fields on the selection-screen of transaction VL06F and also some fields in the report display output.

For displaying fields in the report output, i found one exit EXIT_SAPLV50Q_001, which would serve my purpose. The only doubt I am having is how to add

two parameters on seelction -screen. I tried to enhance the Selection-Screen Include to add the parameters, but on activation it is giving me a short dump

of MESSAGE_TYPE_X.

Please advice is there any way to inlcude these parameters on selection-screen??

Thanks in advance.