I’ve discovered a nasty bug in the Flash CS5 new Text Layout Framework (TLF-Text).
When you type certain characters in a TLF-Text text field, you can get a strange error at compile-time:

Error 1104: Invalid xml name

Since XML is not used in the project we were working on, it didn’t make any sense…

If you use a TLF-Text text field in the Flash IDE, and you type certain characters (in our case “=”) the error starts to appear.
Not sure if this is always the case, but in our case, it triggered the error.

The only workaround I can provide at this time, is to switch the TLF-Text back to Classic-Text.
This off course means loosing the TLF-functionality, but it does stop the error from occurring.