After Update to CB 1.9.1> Error with Space in Username

Hello

Yesterday I made an update to CB 1.9.1. My Joomla version is 2.5.16 . Now I have the problem that when registering the following error message appears:
"Please enter a valid username. No spaces, more than 2 characters and it must not contain the following characters: < > \ . " '% ; () & "
The problem comes from the fact that the username is automatically generated by its first name and surname and in between there is a blank space.
But all worked fine before the update. In the user administration of CB are all user names ("firstname Name") with blank space .

I have made the following settings for the Benutzername/username :
Fields management
Review of the field entry:
Valid entry : Multiple words with space
Configuration
Name fields : first and last name field
Name format : User Only
The user name is not visible in the registration process for the user !

Since it worked until 1.9.0 fine with these settings (75 users have registered over the last 2 years), I have to assume that this is a bug in the new version 1.9.1.

Greetings Eric58

Did you also update your Joomla?

This may be in fact a Joomla issue.

It's OK > A Problem from Joomla 2.5.16

Solution see here (for Joomla 2.5):
www.joomlaportal.de/joomla-2-5-installation/303802-joomla-2-5-16-l-t-im-benutzernamen-keinen-leerschlag-space-mehr-zu.html

Thanks

Eric58

I updated user.php as indicated in Eric58 link.
I updated the preg_match rule and the error disappear.

Thanks

Thanks IT for your help,
i try to not change the core files as all changes will perhaps disappear in the next joomla update. So i hoped that there would be another solution that is not a hack
greets
carsten

I have updated to CB 2.0.1 and now I have the same problem again.
If the Usernames are created automatically from name and surname there isnt't a space between them, there is an underline!

What can I do?

Thanks