Timeout not being respected

Question

Hi,

I am writing a program that downloads websites including caching images.  I have put a 3 second timeout on the request (see link for code).  Despite specifying a timeout the program will occasionally block/hang for a minute or more on the line

myImg = System.Drawing.Image.FromStream(response.GetResponseStream());

http://pastebin.com/JDj72rF2