Question: For some reason when I'm using liferay in internet explorer it does not seem to accept cookies.
So I guess I need to encode my URLs.

I tried `httpUtil.encodeURL('http://x.com/y',true)` but that just gets me <http://x.com/y> again without the JSessionID appended.

Answer: 
I was interested myself to see how it works, this might get you started:

```
Option Infer On

Imports System.Net
Imports System.Web

Module Module1
    Sub Main()
        Dim wc = New WebClient()
        Dim login = "your_login"
        Dim apiKey = "your_apikey"
        Dim longUrl = HttpUtility.UrlEncode("http://stackoverflow.com/questions/4427104/vb-is-there-any-possibility-to-call-the-bit-ly-api")
        Dim request = String.Format("http://api.bit.ly/v3/shorten?login={0}&apiKey={1}&longUrl={2}&format=txt", login, apiKey, longUrl)
        Dim result = wc.DownloadString(request)
    End Sub

End Module

```

The API documentation can be found here: <http://code.google.com/p/bitly-api/wiki/ApiDocumentation>
I found 2 examples where they use bit.ly to shorten url's. Is this what you're looking for?

* <http://www.emadibrahim.com/2009/05/07/shortening-urls-with-bitlys-api-in-net>
* <http://www.fryan0911.com/2009/09/how-to-use-bitly-api-to-shorten-url-in.html>