Wow. Sorry. I didn't knew that it creates an issue report when you send a pull request
You may blame the J!Tracker Application for transmitting this comment.

What is the status of this PR? Any tracker item?

As far as I remember, the PR/commit was made to accommodate the language string which clearly states that there should be no space in the username.

JLIB_DATABASE_ERROR_VALID_AZ09="Please enter a valid username. No spaces, at least %d characters and must <strong>not</strong> contain the following characters: < > \ "_QQ_" ' &#37; ; ( ) &"

(last characters displayed wrong as pasting here changes them)

Also, it corrects some other aspects concerning forbidden characters.
A second PR/commit followed allowing users to reset their username in their profile if there was a space in it.

Just want to agree that this can be a problem for existing 2.5 sites - we have 4K users, a large number of which have spaces and it broke user edit for them... had to revert the users.php file back to the 2.5.14 version in the short term.

Look forward to seeing it fixed in the next update.

can we have a patch vs 2.5.x taking into account both these commits?
07-Oct-2013 Jean-Marie Simonet
# [#30586] Usernames that should not be accepted can be actualy registered. Thanks Sergio Manzi
# [#32199] *Allow username edit in profile edit when username is not compliant. Thanks Achal Aggarwal

• a specific tracker on joomlacode please

I will now make PRs for both 2.5.x and master

Tracker is here
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=32883&start=0

#2643 // master
#2644 // 2.5x

Thanks for testing

Hmm. my PRs are based on this one and this accepts spaces also at beginning and end of username.
What you think?

I'd not allow spaces at the beginning and end of username. I think that could cause too much potential confusion from accidents.

I have modified the PRs to not allow them indeed.
Changed the Lang string to fit. Please test and comment on http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=32883&start=0

new PR for master is
#2646

PR for 2.5.x unchanged #2644

Closing this one as the new ones have now been commited