With the advent of PHP 5.0.x, a new parameter parsing API was introduced
   which is used by a large number of PHP functions. In all versions of PHP
   between 5.0.x and 5.1.x, the handling of integer values was very strict and
   would reject non-well formed numeric values when a PHP function expected an
   integer. These checks have now been relaxed to support non-well formed
   numeric strings such as " 123" and "123 ", and will no longer fail as they
   did under PHP 5.0.x. However, to promote code safety and input validation,
   PHP functions will now emit an E_NOTICE when such
   strings are passed as integers.