Thanks for posting this, Bruno! Can you send a pull request? If you need to learn how, check out this tutorial:
http://docs.joomla.org/Git_for_Coders

I also created a tracker item for this issue:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=30852

You can receive notifications from it by signing in, going to the item, and clicking "Monitor Item" in the left column.

While we’re transitioning to a new integrated tracker, the JoomlaCode tracker is where we do most of Joomla's bug fixing. You can find out more about the process at:
http://docs.joomla.org/Filing_bugs_and_issues

I'm going to close this item, since we have the above JoomlaCode Tracker Item. If and when you submit a pull request, please reference the JoomlaCode Tracker Item URL:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=30852

Let me know if you have any questions and I'll be glad to answer. Thanks again, Bruno!

I am having same issue. maxlength is not working for me when using in plugin xml.

or

Please let me know what need to be done or i am doing wrong.

Thanks in advance..

I am having same issue when using it in plugin xml.

or

Please let me know what need to be done or i am doing wrong.

Thanks in advance.