....
   1102       $sender=~s/\b$P{username}(?!@)//ig;
   1103       $sender=~s/\b$P{email}\b//ig if defined $P{email}; 
   1104       map { $sender=~s/\b$_\b//ig } grep { $aliases{$_} eq $P{username} } keys %aliases;
   1105       $sender=~s/,\s*,/,/g;          
   1106       $sender=~s/,\s*$//;            
   1107       $sender||=$P{username};        
   ....