Merge columns in Excel using Visual c++

Question

I would like to know how can we merge any two colums(cells) and have text on the merged columns in MS Excel programmatically using C++.

We are using Microsoft Visual Studio 2008. The function we use for Excel operations is Autowrap();, e.g.:

AutoWrap(DISPATCH_PROPERTYGET, &result, pXlSheet, L"Range", 1, parm);

in place of range I tried MergeCells, but I didn't get any result.