add media - create folder dialog

Hi all,
I'm curious if there is possibility to validate the input field "new folder name"
I guess related file is media.browser.ejs

<div class="promptForm"><label><?php echo JText::_( 'COM_EASYBLOG_MM_NEW_FOLDER_NAME' ); ?> <input type="text" class="folderInput text" val="" /></label></div>

I don't like the idea to accept utf-8 chars and want to apply an Jquery.replace() script to remove all chars which I want restrict user to type. Or another option - ?