Laptop charger burst into flames?

So I was preparing a little skype session and had my laptop sitting off to one side, not yet connected to the AC adapter. Now this adapter in the past say three days had part of the rubber peel back at one end, as will many slightly used cords, and so I wrapped it heavily in electrical tape merely to prevent further exposure. After connecting the adapter to it's socket component and plugging it in, the adapter began smoking and, subsequently, the socket component cord burst into flame. Now I've not even had this adapter yet a year, and I bought it (cheaply, I might add, which may be an issue) as a replacement to my stock Dell adapter which came with the laptop and has had intermittent connectivity issues, requiring a certain tweaking and placement to transfer charge to the laptop. The burnt AC Adapter in question is PA-1900-02D, and I wanted to ask you fine folks of Yahoo Answers what the best course of action in terms of either replacement or new adapter would be.