We picked up one yesterday on 121.5 too at about that time, and ourselves and a company a/c relayed the message to Brest, although we're neither MyTravel or Globespan so I wonder if it was different 'event'? Hope there wasn't another one.
The mayday callsign we heard gave a position report in both French and English that was somewhere in the region of Nantes. There were no intentions or problem stated in the mayday. About 10 mins later we picked up an intermittent ELT before we switched frequencies. I'm pretty sure it wasn't a commercial aircraft.
I hope the chap made it ok. That's the second one in two days we've heard over France.
411A, I think one engine on a two engine aircraft is serious. Regradless. That increases 10-fold if fire is involved. No engine on a 1 engined aircraft hardly qualifies as being 'wound up like a cheap watch'.
TS6