Dunno if this helps, but audit.log shows the following:
Code:
2008-05-06 16:30:26,140 INFO [btpool0-711] [ip=212.183.134.210;ua=Zimbra Mobile Edition (ZME)/0.5;] security - cmd=Auth; account=alistair.ross@xxxx.com; protocol=soap;
There is no other information in any other logs as far as I can tell with regards to this.