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Can be ignored This happens every 30 seconds. Apparently message is benign
User List Message. Change to debug level in sipXecs 4.6.
"2012-02-15T11:50:28.344501Z":24818:NAT:ERR:swift.hubler.us::7f5535a1b700:SipXProxy:"StunClient::getPublicIpAddress failed to obtain mapping from server stun.ezuce.com"
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