The Sony Ericsson K618i is not a Symbian-based phone, so that's why the Missing Sync doesn't work.
I can't speak for any other downloadable plugins, but the
Feisar K618i iSync Plugin, most definately works. I know, because I developed it...
Julian
Aluminium 20" iMac 2.4Ghz, 4GB RAM Mac OS X (10.6.2)
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