Some variables are not properly initialised and cause strict warnings to be generated.

mod_form.php, line 25, variable $input. Should have a $input=new stdClass;
lib.php, line 927, variable $post should have $post=new stdClass;
lib.php, line 1008, $post again as above
lib.php, line 154, $tiipost as above
lib.php, line 209, $part as above

...and probably others.