How to handle Null Tags in SAP BPM?

Hi,

I have a BPM process model, wherein there are Intermediate Message Events in place which will get triggered from PI.

The PI sends Null Tags when there is no mandatory value to be passed and the BPM is unable to handle it despite the multiplicity of the data object in BPM Context is set to 0..1 .

I have also tried keeping null checks in BPM using nilled keyword , but it always throws a Null Pointer Exception at that process context attribute.

Please share your views on this.

Regards,

Arun