Problems building WebClient

Hi, I'm just trying to build Webclient but i'm having a hard time. I am
working with FireFox 1.8 and everytime I try to run ant on the code it
throws me an exception saying

main:
     [java] Can't init test browser, exception:
java.lang.ClassNotFoundException
: C:\Program Files\Mozilla Firefox\webclient.dll: The specified
procedure could
not be found C:\Program Files\Mozilla Firefox\webclient.dll: The
specified proce
dure could not be found


Can anyone tell me what this error means? Also if anyone knows of a
good step by step walkthrough on how to set up webclient I would be
very appreciative. I had a tough time following the website maybe
because I don't know much about mozilla.
Thanks