valueprompt_objects_disable_regarding

[jagan.dish]

HI Gurus,
                Could you plz help me out here I had the issue from the end user .when they run the report where they  need to select the values prompt objects(e.g we have  countries to be selected say we have 100) but we need not to select all (100 Countires).However in a case if somebody selects all the objects then 'finish' button should get disabled...but I tried by adding script it did not work though I disable 'selectall' option  in properties.

thanks in advance