Invoke C++ method from VB.Net with string handled as string array

I have a C++ method with this signature:

STDMETHODIMP ClassName::FunctionName(long number, BSTR* names, long* status)

Inside the method the names variable is accessed as an array of strings, i.e.

char *  tempString = NULL;

for (int n = 0; n < number; n++)
{
    tempString = OLE2T(names[n]);
...

I compile the C++ project, which generates a dll, I then register this dll and add a reference to it in the VB project. When I add the reference, an Interop assembly is automatically generated, and the signature of the method in the Interop assembly is as follows:

FunctionName (number as Integer, ByRef names as String) As Integer

From VB.Net I invoke the method like this:

result = FunctionName (number, names(0))

Where names is a string array with multiple elements, and number and result are Integers.

The problem is that when the C++ code tries to access the rest of the elements in the names array (names[1] and ahead) it starts getting "garbage" on those fields.

My question is, how do I send the whole string array instead of just the first value.

The C++ code is a library that I cannot modify, therefore any change that I do must be on the VB.Net code.

I was thinking that maybe using PInvoke to call the method might do the trick (declaring a correct signature), but I was hoping for something better.

Any ideas?

Thanks!

Edit:

I'm no expert in Interop/Marshaling but I checked the IDL definition of the method and it is as follows:

[id(60), helpstring("method FunctionName")]
        HRESULT FunctionName(
                    [in] long number, 
                    [in, size_is(number)] BSTR* names,
                    [out, retval] long* status);

Shouldn't the size_is indicate that the names parameter is an array, and thus, when the Interop assembly is generated act accordingly?

Thanks again