I have a customer who has Release 6.0.5_GA_2213.UBUNTU8 UBUNTU8 FOSS edition installed on Ubuntu 8.04.2 LTS, and they are recieving the following error when trying to send email from the Zimbra interface. I have restarted Zimbra, and postfix, and checked the MTA details but none of this has resolved the issue. Can any forum members suggest a solution or at least provide some pointers to a solution?.

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method: SendMsgRequest
msg: system failure: Unable to get SMTP session for [com.zimbra.cs.account.ldap.LdapAccount dc123@cubusconcepts.com.au]
code: service.FAILURE
detail: soap:Receiver
trace: btpool0-4://mail.cubusconcepts.com.au:82/service/soap/SendMsgRequest:1269416148316:1d892584b8539784
request:

Body: {
SendMsgRequest: {
_jsns: "urn:zimbraMail",
m: {
e: [
0: {
a: "chrisg@dc123.com",
t: "t"
},
1: {
a: "dc123@cubusconcepts.com.au",
t: "f"
}
],
idnt: "7b1d70a1-6201-4e38-9272-1a41eee831ff",
mp: [
0: {
content: {
_content: ""
},
ct: "text/plain"
}
],
su: {
_content: "test"
}
},
suid: 1269416149191
}
},
Header: {
context: {
_jsns: "urn:zimbra",
account: {
_content: "dc123@cubusconcepts.com.au",
by: "name"
},
authToken: "(removed)",
notify: {
seq: 1
},
session: {
_content: 112,
id: 112
},
userAgent: {
name: "ZimbraWebClient - FF3.0 (Linux)",
version: "6.0.5_GA_2213.UBUNTU8"
}
}
}