Using Web.HttpContext.Current.Cache in windows app

Hi
I have a component (vb.net class project) which is used by both a web app
and windows app. But it uses Web.HttpContext.Current.Cache , works fine
in the web app but refuses to work in the windows app, even with all the
correct references. Just gives and Null Reference error.

What needs to be done to get Web.HttpContext.Current.Cache to work in the
windows app environment?

Any help would be appreciated :)