[Serusers] SIP response 403

I am trying to make an outgoing call to another iptel account using Asterisk. I have followed a how-to for asterisk and iptel found at http://www.voip-info.org/tiki-index.php?page=Asterisk%20sip%20client%20SER I am getting the following error message: Got SIP response 403 "That is ugly -- use From=id next time (OB)" back from 195.37.77.101 I'm not quite sure what that means. Does anybody know what I might have done wrong? Here is my configuration: sip.conf register => account:passwd@iptel.org/ [iptel] type=friend username=account secret=passwd host=iptel.org extensions.conf exten=>_3.,1,SetCallerID(myNumber) exten=>_3.,2,SetCIDName("myName") exten=>_3.,3,Dial,SIP/${EXTEN:1}@iptel exten=>_3.,4,Playback(pbx-invalid) exten=>_3.,5,Hangup Thank you for your time. __________________________________ Do you Yahoo!? New Yahoo! Photos - easier uploading and sharing. http://photos.yahoo.com/