Using Type (Date and Value) set to Null in the Variables window, result is blank (4308134)

When I run a query (see example below) that asks for a variable, and I use Type: Date and Value: Null in the Variables window, the result is blank. It should return with the result "true". In older versions of Toad for Oracle, this works fine.

SELECT 'true' FROM dual WHERE :x is NULL

WORKAROUND:
None

Status:
Waiting for fix in a future release of Toad for Oracle.

STEPS TO DUPLICATE:

1) Run [SELECT 'true' FROM dual WHERE :x is NULL] in SQL Editor using F9 (Execute Statement)
2) The Variables Window will appear
3) Change the "Type" field to "Date"
4) Do not enter anything in the "Value" field
5) Click OK
6) Nothing is returned in the results data grid. It's just blank. It should return the value "true" in the data grid.
7) If the "Type" field is changed to "String", "true" is returned as a result in the data grid
8) In Toad 8.6.1, "true" result is returned no matter  "Date" or "String" is chosen in the "Type" field