Reflection Method Invoke - Failed to convert parameters

I have a static method that has the signature:

pubic static foo (float,float,IEnumberable<IEnumberable<double>>)

I'm using reflection to call this method with arguments of

int, int, and List<List<double>>, 

this fails, it appears to me that the List<List<double>> parameter is failing to be converted. I'm using the code below to attempt to convert parameters

Is this possible? A limitation of reflection? I would have thought that List implemented the IEnumerable interface and would just work.

var args = inputportvals.Select(x=>
                             {
            if (x.First is IronPython.Runtime.List || x.First is IDynamicMetaObjectProvider)
            {
                return x.First;
            }

            if (x.First is IEnumerable || x.First is IList)
            {
                return x.First as IEnumerable;
            }

            else
            {
                return Convert.ChangeType(x.First, infos.Where(y=>y.Name == x.Second).First().ParameterType);
            }
        }
        ).ToArray();


funcdef.MethodPointer.Invoke(null,args);