Resolved.

It was not a perl issue. It was weirdness with the extended ascii character set that is used by Windows and the MacOS. And with the way that Flash needs to receive special ascii characters in order to display them properly.

For those who are interested, Flash 5 will display any ascii character if it is encoded as hex, and preceeded by a percent sign. So "trademark" is %ae, e.g. Thanks to everyone who puzzled over this...