It appears, that in 32bit OS ip2long returns signed int, and in 64bit OS unsigned int is returned.
ip2long
My application is working on 10 servers, and some are
interpreting an integer value as signed int on 32 and 64 bit systems:
function signedint32($value) { $i = (int)$value; if (PHP_INT_SIZE > 4) // e.g. php 64bit if($i & 0x80000000) // is negative return $i - 0x100000000; return $i; }