The Mégane II Owners' Club

I have a Megane 2005 and this morning when i was driving it the car started to make a ridiculous sound as if there was something wrong. Later i realised it wont go into reverse gear. I have been told the gear box is gone by one mechanic and another has said it could be due to electrics. Can anyone help on this matter please.

Thanks

Electrics sound VERY unlikely - although I would be pleased to be proved wrong. I take it that the clutch is okay?

What precisely were the diagnoses from the mechanics?