Integration of Mathcad with AutoCAD thro VB.NET

I am using Autocad 2010 to get values of variables in a MathCAD program using VB.NET. what is the string value in GetValue for a MathCAD variable that is a Greek letter? Even I have gone Developer Help-getvalue it may work in VBscript but what about VB.NET. i tried but in vain. Please help.