* gnus-art.el (gnus-button-url-regexp): Revert earlier change.
Recognize domain names starting with `www.' as starting an URL.
;;; Internal Variables:
-(defcustom gnus-button-url-regexp "\\b\\(\\(s?https?\\|ftp\\|file\\|gopher\\|news\\|telnet\\|wais\\|mailto\\):\\(//[-a-zA-Z0-9_.]+:[0-9]*\\)?\\([-a-zA-Z0-9_=!?#$@~`%&*+|\\/:;.,]\\|\\w\\)+\\([-a-zA-Z0-9_=#$@~`%&*+|\\/]\\|\\w\\)\\)\\|[-a-zA-Z0-9_]+\\.[-a-zA-Z0-9_]+\\(\\.[-a-zA-Z0-9_]+[-a-zA-Z0-9_/]+\\)+"
+(defcustom gnus-button-url-regexp "\\b\\(\\(www\\.\\|\\(s?https?\\|ftp\\|file\\|gopher\\|news\\|telnet\\|wais\\|mailto\\):\\)\\(//[-a-zA-Z0-9_.]+:[0-9]*\\)?\\([-a-zA-Z0-9_=!?#$@~`%&*+|\\/:;.,]\\|\\w\\)+\\([-a-zA-Z0-9_=#$@~`%&*+|\\/]\\|\\w\\)\\)"
"Regular expression that matches URLs."
:group 'gnus-article-buttons
:type 'regexp)