Due to an unforeseen side-effect of the attempt at compiled code patching back in January it appears that the newly patched Trinity 1.0.2 client was still using the downloaded compiled.code from the hotfix in January, and thus the machonet version number did not match.

If you are getting the error "Incompatible (Protocol)" when trying to connect to Tranquility post Trinity 1.0.2 patch, it is because of this previous patch.
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http://myeve.eve-online.com/news.asp?a= ... 1793&tid=1