Calendar Notification Issue

[Johannes Graumann]

Hello,

I switched my kontact standard sender account over to google, since my kolab
server is running on a dsl-subnet (using dyndns) and to many mail servers
block that subnet as spam. Now I get the following error when trying to
send an appointment notification to ather colab users:

> This is an automatically generated Delivery Status Notification
> 
> Delivery to the following recipient failed permanently:
> 
>      otheruser at mykolab.net
> 
> Technical details of permanent failure: 
> PERM_FAILURE: SMTP Error (state 9): 554 <me at googlemail.com>: Sender 
> address rejected: Access denied 

Can anybody enlighten me how to fix this - and what I screwed up?

Thanks, Joh