This problem result in using E_STRICT error reporting enabled in your php.ini. E_STRICT was added to php with version 5. With version 6 E_STRICT is also member of E_ALL so php-suger should develop with E_ALL and E_STRICT warnings on!
I've correct all three of these errors, as well as fixed up some tests and added a new one for comments. These fixes are in SVN, and will be in the 0.73 release.