Best OSX SIP softphone?

[FP]

Is anyone using a softphone app on their Mac? I have a SIP PBX set up and just need the softphone. I normally use XLite on my PC but it doesn't want to cooperate with OSX.

Suggestions?

 

[aphex]

Curious as well. I have fring on my iPhone which supports SIP and Skype, but I don't have an app on my Macbook.

 

[FP]

I was finally able to get X-Lite to work on my MacBook. I had to disable the QoS settings and hard-code my external IP address instead of letting it discover it with a STUN server.