IB Scale Order problems

I was hoping that someone here on ET has used TWS Scale Orders through the API. Here is what I see.

I submit orders as follows (e.g.):

order.m_totalQuantity = 500
order.m_orderType = "SCALE";
order.m_scaleComponentSize = 100;
order.m_scalePriceIncrement= 0.01;

In return I get the following error message:
Error validating request:-'ob' : cause - Invalid order type was entered

And the log contains the following entry (stack dump):

JI 09:46:41:713 JTS-EServerSocket-821: Null error type from SCALE
JI 09:46:41:714 JTS-EServerSocket-821: [1:37:39:1:0:0:0:ERR] -'ob' : cause - Invalid order type was entered
JI 09:46:41:714 JTS-EServerSocket-821: Anticipated error
JI jextend.d: Invalid order type was entered
at jextend.ob.d(ob.java:671)
at jextend.v.h(v.java:227)
at jextend.id.H(id.java:657)
at jextend.id.run(id.java:531)
at java.lang.Thread.run(Unknown Source)

I'm on TWS=882.2 and API=9.4.

Any insights on what could be causing this, would be much appreciated.