Joomla 1.6 index files attack with line code

Hi,

Yesterday my website was hacked in all the index files with the line code " <img heigth="1" width="1" border="0" src="httd://myteenmovies.net/t.php?id=5454873"> " (i change the http)
I search about this hack in google, with no results.
I have the first version of Joomla 1.6...so dont forget to upgrade your joomla version.

Be alert...
Cheers,
Luis