Placeholder shown on email tpl

Maybe there is a bug in filling the placeholder for the email tpl? Empty placeholder dont get replaced before sending, so it looks like this:

Deine Bewerbung	[[!+fi.field_20]]
Stellenausschreibung	Initiativbewerbung
Deine Kontaktdaten	[[!+fi.field_21]]
Anrede	Herr
Vorname	Jens
Nachname	Wittmann

This appears for headings and fields with no value. Someone get an idea to fix this? (: