Assegnate 2 su 5 stelle

Hello, this sounded great. so I downloaded it. Unfortunately it doesn't work. On clicking options (in the list with addons) I got XML-parsefout: ongedefinieerde entiteit
Locatie: chrome://senderface/content/prefs.xul
Regelnummer 55, kolom 11: <listheader id="emailCol" label="&sf.pref.email.from.regex;"/>
----------^ on my screen. Any help please?
thx
Björn
Belgium