This last link was the good one! Thanks so much Fari!

I forgot to mention: publish_up collation is empty

Thanks Fari! I have tried the updated solution but it's not working. I forgot to mention that my query also retrieves the introtext field in which I have special characters. The special characters in introtext are correctly displayed, I only have a problem with the one in publish_up. So I guess, that can't be due to the encoding of the file.

Thanks moomoochoo! I have try to set the the publish_up collation to utf8_general_ci (same collation I used for introtext in which I have special characters) but the database seems to not be able to process the change. Is it because the field type is DATETIME (instead of mediumtext for introtex)? I am afraid I can't change the field type for publish_up to mediumtext without seriously interfering with the Joomla structure.

:)! There are so many things that are still a great mystery to me, that you can be sure I will stick around to ask questions and get more tricks!

Great! Thanks so much David for your answer and for all your advices. It's working great! I didn't know about the #__ trick: that's really cool! I will dig into the Joomla's query object to improve my codes! Thanks again David!

So simple and so stupid! Thanks a lot Lodder!