[horde] Problem with sending mail via mobile interface

[Jens Grüntjes]

Hello list,

when I send a mail via smartphone I receive an error message saying  
"Beim Versenden der Nachricht ist ein Fehler aufgetreten: Ungültige  
E-Mail-Adresse ( )." In English it means something like "Error while  
sending mail: Invalid E-Mail-Address ( )." (Sorry, I could not get the  
english message because changing the language at the login page seems  
to be overwritten by some preference I guess, so the error message is  
in german.)

Obviously the E-Mail-Address is empty. In the Horde-Logfile I find the  
following entry

2012-10-31T09:49:04+00:00 ERR: HORDE [imp] Ungültige E-Mail-Adresse  
( ). [pid 10135 on line 1155 of "/var/www/horde/imp/lib/Compose.php"]

It is interesting that the mail is however sent to the recipient but  
does *not* show up in my sent-mail folder. Did I misconfigure something?

Thanks for your help
-- 
Viele Grüße
Jens