Here at work we had a problem similar to the one described by Gentle in another thread: xBench and TM maintenance.
To deal with the problem of strange characters we used jEdit, which is a very robust text editor written in Java which has a thorough understanding of character encodings.
For the combo XBench-JEdit to work properly, we have to go to Tools->Settings->TMX Editor, choose the path to the JEdit executable and (the crucial part) write the following in the "Command-line parameters" box:
Another thing to be careful about is to be sure that the JEdit server is running, otherwise all kind of problems occur.Code:$Filename +line:$Line
So, Gentle, try this out and let us know if it worked for you.