I asked this in another thread but there was no response and it was a bit off topic anyway.

Basically I'm wondering if skaven fire at a skirmishing unit in melee, is there any rule stating that the skirmishers are not still -1 to hit? It seems a bit odd to me that a skirmishing unit ranked up and fighting would get this bonus, particularly when it means that the skaven they are fighting also, for all practical purposes, suddenly have -1 to hit since you must target the enemy unit. Still, I can't think of any rules stating otherwise, and I can't find any clarification in the Skaven rule book.

Any ideas?