Error When Passing Multiple Values from a Parameter

For large LOVs, I would like to pass NULL to the parameter when users select All & modify WHERE clause in Data Set query to use the NVL function. For example: “Where order_id=nvl(:p_ordid, order_id)”. 

However, for some reason this does not work when combining “Multiple Selection” and “Select All - Null Value Passed”.    The select all works fine, passing a single value works fine, but whenever I try to select multiple values, I get “Error on retrieving data xml” message.   I have tried “IN”, instead of “=“ and that didn’t make a difference.

I have ran into this problem multiple times on different reports, but haven’t been able to get it to work, so I suspect that there may be a bug.      For small LOV’s combining “Multiple Selection” and “Select ALL” (without passing Null) seems to work fine.