Description:
------------
With the functions 
mcrypt_encrypt, mcrypt_decrypt with MCRYPT_MODE_ECB and mcrypt_ecb, by not providing an initial vector or providing one that isn't at the correct block size results in a warning being generated. 

ECB mode never uses the initial vector, so a warning is irrelevant. 

Reproduce code:
---------------
<?php
// the same type of results can also be seen with mcrypt_ecb, mcrypt_decrypt
var_dump(bin2hex(mcrypt_encrypt(MCRYPT_TRIPLEDES, "key", "data", MCRYPT_MODE_ECB)));
var_dump(bin2hex(mcrypt_encrypt(MCRYPT_TRIPLEDES, "key", "data", MCRYPT_MODE_ECB, "a")));
var_dump(bin2hex(mcrypt_encrypt(MCRYPT_TRIPLEDES, "key", "data", MCRYPT_MODE_ECB, "12345678")));
?> 

Expected result:
----------------
string(16) "372eeb4a524b8d31"
string(16) "372eeb4a524b8d31"
string(16) "372eeb4a524b8d31"

Actual result:
--------------
Warning: mcrypt_encrypt(): Attempt to use an empty IV, which is NOT recommend in C:\udata-eclipse\p8\a.phpcode\mcrypt_ecb.php on line 2
string(16) "372eeb4a524b8d31"

Warning: mcrypt_encrypt(): The IV parameter must be as long as the blocksize in C:\udata-eclipse\p8\a.phpcode\mcrypt_ecb.php on line 3
string(16) "372eeb4a524b8d31"
string(16) "372eeb4a524b8d31"