Hello,
for joomla 2.5
I am working on a site which is in two languages, Greek and English.
I notice that when a visitor post a comment in an item, this goes only in the language that is posted..
I would like to have the comments in both languages. Is there a way to solve this issue?

Hi. This depends on how you have setup your multilingual environment. If you are using Joomla! core multilingual features then this cannot be done since each translation is a different K2 item. If you use Falang or JoomFish for translations then comments will be displayed automatically in both languages.