Hi, abilio:
I believe you are seeing a cursor setting like "crosshairs" enabled in sketchup--Go to Window>Preferences>Drawing> in the panel, check/ enable crosshairs.
Hey, that's it! Thanks a lot, l thought it was a plugin...
No problem abilio. It's nice to be able to share some experiences and learn some things in the process. I've never used andybot's tip about the polyline divider before either but that sounds like it could pretty helpful in a number of situations. I hope I can remember that one for next time.