private methods require an underscore

Hello QAers! phpcs frequenty complains with the following message: Private method name "Foo::getS3AuthCode" must be prefixed with an underscore (getS3AuthCode is a private method in Foo.) I believe the underscore is redundant in PHP5 - kind of like @access tags in phpdoc in php5 so I wouldn't use it, others suggested the same. I don't want to just go ahead, because I want all the shiny CS graphs to be at 0. ;-) Any advice? Or should I open a feature request? It could probably take "PHP Version X" from the file comment and act based on that? (My first guess to resolve this issue within phpcs.) Thanks and regards, Till