$Torrentz_Interface->submit_form(
        form_number => 1,
        fields      => {
            user       => $username,
            pass       => $password,
        }
    );

##</code><code>##

<form action="/profile" method="post" class="profile">
<fieldset>
<legend>User Login</legend>
<label for="luser">Username</label>

<input name="user" id="luser" class="i" type="text">
<label for="lpass">Password</label>
<input name="pass" id="lpass" class="i" type="password">
<div class="s"><input name="go" value="Login" type="submit"></div>
</fieldset>
</form>

##</code><code>##

torrentz$ mech-dump http://www.torrentz.com/profile
POST http://www.torrentz.com/profile
  user=                          (text)
  pass=                          (password)
  go=Login                       (submit)