OIC REST Outbound File - How to pass NULL values?

Hello,

We need to pass NULL values in the output JSON file generated through OIC REST Integration. Currently JSON attributes prints NULL in the following manner.

ExemptStatus: 'NULL'

As you can see, this is not null, it is a string.

Our requirement is to pass null values as per the following.

Either :

ExemptStatus:

OR

ExemptStatus: null

How can I achieve that in OIC, can someone provide steps and navigation?