error message as post title when posting announcement on ES

Hello,

i just posted a new announcement on ES and have this error message :
Warning: sprintf(): Too few arguments in /home/.../libraries/joomla/language/text.php on line 312

+ also lines break are missing in the stream post :
http://awesomescreenshot.com/0a35dopt92

thanks in advance for your help
Loïc

nota : using last ES and last language file