OData in JSON

Experts:

I've looked to see if this question had been answered RECENTLY and there hasn't been an update in years.

I'm running a NetWeaver 7.4 SP10 system with an embedded Gateway.  My BW queries are being activated as oData services through the BW query designer.

I am finding that I cannot use $format=JSON.  I get

"The statement could not be formed due to malformed syntax"

My call is here:

/sap/opu/odata/sap/ygmh_b0activity_q0005_srv/YGMH_B0ACTIVITY_Q0005(BCUPRJNWAM='V1000868',BCUPRJNWAMTo='')/Results?$format=JSON

So my questions are:

Does NW 7.4 support oData in JSON format?  If so, what am I doing wrong with the format of the URL encoding?

Thank you!

George