Bear with me, I'm new to NUnit. I come from the land of Rails, so some of this is new to me.

I have a line of code that looks like this:

```
var code = WebSiteConfiguration.Instance.getCodeByCodeNameAndType("CATALOG_Brands_MinQty", item.Catalog);

```

I'm trying to mock it, like this (assume `code` is already initialized):

```
var _websiteConfigurationMock = new DynamicMock(typeof(WebSiteConfiguration));
_websiteConfigurationMock.ExpectAndReturn("getCodeByCodeNameAndType", code);

```

When I debug the test, `getCodeByCodeNameAndType` is returning `null`, instead of the expected `code`. What am I doing wrong?

NUnit version: 2.2.8