Setting value of a indexed property of an OLE object

I suspect this question is not directly related by Rails but perhaps Ruby users on this list know an answer for this

I have an OLE object which has an indexed property on it (something like a dictionary).
In C# (or similar languages) I set the value of one of the elements in the indexed property such as this

MyOLEObject myObject = new MyOLEObject();
myObject[“property name”] = “property value”;

using ruby Win32Ole api, if I use square brackets as I use in C#, I get
the error " Unkown property or method ‘property name’ ".
I suspect this is because ruby Win32Ole api tries to set a real propery on the object such as name = “property value” which is not possible.

Can you give me any directions about how to solve this problem, aka setting an indexed property through Win32OleApi