Prevent character from moving after selecting target.

[Astos]

Sorry if it has been answered somewhere else, but I couldn't find it.
To put it simple, I added charge times to the Holy/Dark Swordskills. It works fine, except for the fact that the player chan choose a target and then move away from it. It's the default behaviour for most ranged skills (Black magic, for example, let's you start casting then walk away) but it doens't make much sense for sword attacks.
Cloud's limits and Archer's Charge do block movement after selecting a target, but I can't seem to reproduce that in other skills. Is there a flag I'm missing?