Shield of Warding question

[Blu C Fox]

Shield of warding gives +1 to a shield and another +1 per 5 caster levels, maxing out at +5 at level 20.

However I was under the impression that a paladin's caster level is considered to be half their total paladin levels. Which would mean that a Paladin's maximum caster level, assuming they take no other classes, is 15 at level 30, preventing them from ever getting the maximum +5.

Is this intentional?

[Luna]

We forgot to update the description of the spell.
It's intentional it does not go to +5.