Description:
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Function checkdate(mon, day, year) accepts float values as valid parameters.

Reproduce code:
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$day1 = 13.7;
$mon1 = 5.1;
$year1 = 2000.75;

if (checkdate($mon1, $day1, $year1))
  echo "Valid date";
else
  echo "Invalid date";

$day2 = "4e4";
$mon2 = 5.1;
$year2 = "2000.75";

if (checkdate($mon2, $day2, $year2))
  echo "Valid date";
else
  echo "Invalid date";


Expected result:
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I expected the script to echo two times 'Invalid date' since only integer parameters should be accepted.

Actual result:
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The script echoed two times 'Valid date'. The first date is a clear case. I guess the second date is considered valid because of the string "4e4" being taken as "4" (the number 4), which is also wrong.