On second thought, who am I kidding, they probably are.
I doubt that the government will act on an early warning system any time soon. You see, it has no money to complete projects already at hand. No corporation will want to pick up this profitless tab. With all the money split up between PASOK, New Democracy, KKE, and Synapsismos robber baron political system the country can barely finish projects in progress. I think it the sum of the tax payers wealth went to 1 part SYN, 2 parts KKE, 3 part new Democracy, and 4 parts PASOK.
I say a cheaper way is to have pamphlets up everywhere in the coastal areas detailing how the sea appears when a tsunami is in the works. The ancient Hellenes have already provided the material.
Also, this page deals with the issue of an early warning system in the Aegan. I am copying here the bad site design makes the text unreadable..
A tsunami warning system in south-west Aegean Sea, Greece
Gerassimos A. Papadopoulos
Abstract: One of the most tsunamigenic regions of Europe is the Kythira Strait
between Peloponnesus and Crete Island. Large, destructive tsunamis have been
reported there in historical times such as the waves of 66 A.D., 365, 1630 and
1866, all of them being associated with respective large earthquakes. Future
tsunamis to be generated in that area could cause near-field as well as
far-field effects. Since the tsunami travel times are locally very short,
near-field effects are expected within only about 10 min from the tsunami origin
time. Therefore, the Greek research team that is participating in GITEC-TWO has
selected the Kythira Strait, SW Aegean Sea, for the development of a local
tsunami warning system (TWS). Before establishing such a TWS its operational
efficiency should be firstly tested by considering its response capability. The
main purpose of the test is to evaluate the maximum alert time, that is the time
interval between the origin time of a potentially tsunamigenic strong earthquake
and the maximum acceptable time for setting up a tsunami alert. To this goal an
experimental system for monitoring the earthquake activity and the sea level
changes has been developed. The system consists of a number of digital
seismographs and tide-gauges. A 24-hour operation of the system and an on-line
data transmission and automatic elaboration at the Institute of Geodynamics,
Athens, has been scheduled.