Description:
------------
PHP uses in the ip2long() function the obsolete inet_addr() interface which makes it impossible to detect errors in the input values: inet_addr() converts 255.255.255.255 to -1, which is correct. But in error case it also returns INADDR_NONE, wich is usually defined as -1. Therefore the inet_aton() function should be used. I made a little patch which corrects this.

Actual result:
--------------
1223a1224
>   struct in_addr in;
1231c1232,1237
<       RETURN_LONG(ntohl(inet_addr(Z_STRVAL_PP(str))));
---
>   if(inet_aton(Z_STRVAL_PP(str),&inp) == 0) {
>     php_error_docref(NULL TSRMLS_CC, E_WARNING, "Invalid address");
>     RETURN_NULL();
>   }
> 
>   RETURN_LONG(ntohl(inp.s_addr));