The last post was of interest and thanks -

I never realized to make both sides invisible. On phone go to bluetooth then hidden (on my Samsung M500) or whatever.

On my N810 and I hadnt done this up to now. Click on bluetooth icon or control panel- bluetooth and UNcheck visible.

You are now invisible as in not visible

Now that I have some more experience with my bt and Nokia I feel more secure with my N810, however I still wonder how I was able to log into someone's phone without permission.
This also brings up
http://www.internettablettalk.com/fo...013#post190013

which would be a dandy way to listen in on someone with a bt headset.

Wrong.

It's more difficult if you're not discoverable, as then they have to know your BT MAC. But that can be found (with reasonably cheap tools) anyway if you're connected to your own phone, headset etc., and if it's already known by whatever method (a previous one-time connection for OBEX transfer, or even old-fashioned snoopage under the battery cover), then that elimnates the need for other equipment or an existing connection on your end.

#2 still stops them, though; and #1 stops casual idiots from spamming you with connection requests, so do it, but know what it does for you, and what it doesn't.