I'm not sure if this is a bug or by design, but if a character has 0 xp in a skill, and applies a skill item (such as a writing pen or holy symbol) I would expect the skills command to also include that skill, even at 0 xp.
I would also expect the server to send the skill as part of the stats protocol message, and maybe even remove it if the skill item was unequipped before any xp was granted to said skill.