If you're at work and using company property (phone), then it's legal.
Legalities? I would think the company should make all its employees aware that their conversations could be monitored. And - what the company does with the 'information they're listening to' is another story.
Where I work, before you log into the computer....there's a huge disclaimer and you have to click OK before actually logging in. The computers & everything else must only be used for business purposes. We have internet access, e-mails, etc. They have the right to look & read everything you're doing and take notice to all websites that you visit. The company is pretty good about it.....as long as its not interfering with your job. Facebook, Myspace and even Ebay
have been restricted from the work computers. Anytime a site gets too much traffic from work, they restrict access.
You can get online and do normal browsing. It's the inappropriate stuff they don't like.
And yeah....people have gotten FIRED because they were visiting 'inappropriate' sites while at work. That's a major NO-NO. Big brother does watch....and they walk your ass out without any warning.