Command /give @p skull 1 3 {SkullOwner:<playername>} doesn't support numbers

Typing a command "/give @p skull 1 3

{SkullOwner:<playername>}

" doesn't suport numbers.

Steps to reproduce:
1. Type: /give @p skull 1 3

{SkullOwner:107295}

2. You will notice that you get a normal "Steve" head. (107295 is a player's username)