Duelpersonality said:True, but that's not what the ability actually says. Besides, by this point a longsword is a wand for the character, so it's not entirely inappropriate even thematically.
"Using your blend of martial prowess and arcane might, you infuse your blade with added swiftness, striking your opponent with ease."
You must be wielding your wand to gain the bonus. If you're making a longsword attack, you're wielding a longsword, not a wand. I'm pretty sure I saw Mearls specifically define "wield" as "make an attack using" somewhere around here.