ToME: the Tales of Maj'Eyal

Would it be possible to create the target designator for controlled phase door and/or teleport spells so that tiles which are "no-teleport" would not be included or would be in a different color? Thus giving an indication when a phase door attempt would potentially fail?

Judging by the way teleport spells are written I don't think the character is supposed to know he's in a no teleport area or targeting a no teleport zone. It autofails if you try to teleport and returns as though you used the talent.