I know this is old, but check out this site, it is definitely possible.
This posts lists the following parameters:
ptable0 – This parameter corresponds to the main object in your
report. I haven’t quite figured out what goes here, but it seems to be
CUST_ID for custom objects and [OBJECT NAME]_ID for standard objects.
ocond0 – Use w for with and wo for without
rtable0 – This is the cross filtered object. It should be the object
name for standard objects and the object ID for custom ones.
rtablecol0 – This is the column on the cross filtered object that
corresponds to the parent object. For standard objects, use the field
name and and for custom objects, use the field ID.
sfpc0_0 – This is the field to filter on. For standard objects, use
the field name and and for custom objects, use the field ID.
sfpn0_0 – This is the filter operator. It can be values such as eq,
ne, gt, lt, ge, le.
sfpv0_0 – This is the value you want to filter on.