The new versions of messenger only allow video chat. If you want one way calling please uninstall messenger:
Start > (In XP, click Run) > Type in the following & press enter:
msiexec /x {B57EAFF2-D6EE-4C6C-9175-ED9F17BFC1BC}
Follow instructions to uninstall WLM.
Once you have done this install this version of messenger:
http://messenger.jonathankay.com/redir/w3qfe2/wlm.asp
It should now work as it did before. In the new WLM 2010/2011 there will also be no one way chat, only video calls

. You can give feedback to Live about this and tell them anything you disagree with:
http://feedback.live.com/