Guys.. it seems that you got a vulnerability in /lib folder... in my case it was in main.php if I remember well.
My website was hacked based on that.. exploited on one of the java script file that your programm has.
I lost everything on it.. and there was hard work.. believe me. i have to start all from 0 as far as I didn't have a backup (which is my f**cking fault).
After they injected the code I received the following error:
http://img685.imageshack.us/img685/3727/errorsite.jpg
You might have a look on the plugin codding again and fix it.
Personally I won't use wassup for my web-blog anymore.
Wanted to report it.. maybe's useful for you.
Cheers.