On January 21, 2012 at 18:45, tweeterguy said...
In this case, nothing other than dropping that node and any other it's connected to to 100 megabit. Nothing detrimental will occur as both ends of the cables pin 7 and 8 will be broken out. So unless they need gigabit interconnectivity between this node or even more doubtfully a gigabit connection to the WAN, this is the way to go; using pair 4 for the telephone.
I guess all I was trying to get at, it's the same issue as wiring anything incorrectly, someday it's going to come back and get you (actually your customer). I guess one thing you could do is label the wallplates with a warning sticker stating that this connection from x to y is not wired right, if that's done I see less of a problem with it. There are CAT5 devices besides GB that use those pairs.
