I encountered this a few weeks back on another forum. While fictional,
it was to be regarded as within the realm of possibility, but objections
were immediately raised as to the ability of a 109 to get that far. This
led me to this site:
http://www.csn.ul.ie/~dan/war/crashes.htmsummary of all foreign landings & crashes in Ireland 39-45. Not a LW fighter among them.
All multi-engine - a few 111s and 88s, some transports and a couple of bv138 amphibians.
Mostly lost, some damaged and straggling.
A 109 would have been extremely unlikely to have been able to reach there,
no matter how lost. I believe if it started out from the furthest NW Normandy
field and headed straight for Wexford with no diversions, it might just make it.