Special characters

[eluser]Unknown[/eluser]
I have a username called ‘phil.aarthikaindia’, it gets converted to ‘phil_aarthikaindia’

'.' is being replaced by '_', but couldn’t find any.

any help will be highly appreciated

thanks

[eluser]Thorpe Obazee[/eluser]
It's much better if you can say how and when the 'username' is modified. You can probably post some code.