Addthis Button in E-Mail - Customizing

I am using Addthis service in my email marketing. It works fine but I would like to change one thing. When you Click the Tweet Button You get a screen that says:

 http://bit.ly/... via @addthis

My question is can I change the "via" from @Addthis to my username? Also is there a way to pull the subject into the text? Here is the code for just the tweet part of the overall button:

<a href="http://api.addthis.com/oexchange/0.8/forward/twitter/offer?pco=tbxnj
-1.0&amp;url=http%3A%2F%2Fwww.example.com&amp;pubid=ra-" 
target="_blank" ><img src="http://cache.addthis.com/icons/v1/thumbs/
twitter.gif" border="0" alt="Twitter" /></a>

The code below is the full code for the Addthis button:

<!-- AddThis Button BEGIN -->
<a href="http://api.addthis.com/oexchange/0.8/forward/facebook/offer?pco=tbxnj
-1.0&amp;url=http%3A%2F%2Fwww.example.com&amp;pubid=ra-" 
target="开发者_如何学编程_blank" ><img src="http://cache.addthis.com/icons/v1/thumbs/
facebook.gif" border="0" alt="Facebook" /></a>
<a href="http://api.addthis.com/oexchange/0.8/forward/twitter/offer?pco=tbxnj
-1.0&amp;url=http%3A%2F%2Fwww.example.com&amp;pubid=ra-" 
target="_blank" ><img src="http://cache.addthis.com/icons/v1/thumbs/
twitter.gif" border="0" alt="Twitter" /></a>
<a href="http://www.addthis.com/bookmark.php?source=tbxnj-1.0&amp;=250&amp;
pubid=ra-&amp;url=http%3A%2F%2Fwww.example.com " target="_blank"
><img src="http://cache.addthis.com/icons/v1/thumbs/more.gif" border="0" 
alt="More..." /></a>
<!-- AddThis Button END -->

Thanks for the help.

---

My question is can I change the "via" from @Addthis to my username?

Here you go :

<a href="http://api.addthis.com/oexchange/0.8/forward/twitter/offer?pco=tbxnj
-1.0&url=http%3A%2F%2Fwww.example.com&pubid=ra-4dfb00d56c76d2a5&via=Lynda" 
target="_blank" ><img src="http://cache.addthis.com/icons/v1/thumbs/
twitter.gif" border="0" alt="Twitter"/></a>

I added

&via=Lynda

to the end. You would change "Lynda" to be whatever you want.