The former Republic of Ireland international has signed on a non-contract basis.
The 35-year old, who has also played for Crystal Palace and Birmingham City, left Colchester United at the end of last season.
The striker is available to play for the Grecians in their League Two game at Accrington Stanley tomorrow night.
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Labour tightens grip on Plymouth City Council power
They've gained nine extra seats
Labour retains control of Exeter City Council
Despite losing a seat to the Greens and an independent
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Devon voters go to the polls
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