Thanks I answered the last question by myself by doing a little "trial and error playing around" with xowiki-plainpages and iframe-TAG.
Using ADP-Pages in xowiki, like you stated in your first paragraph.
Do I understand the syntax correctly that one can show ANY ADP-Page from xowiki.
So, the ADP-Page /dotlrn/classes/kfm/bhak_eisenstadt.0AK_ENWS_F.s0708/calendar/view?list_of_calendar_ids=6197699&period_days=100&view=list
should be accessed by xowiki-adp-includelets with:
{{adp /packages/calendar/www/view-list-display {list_of_calendar_ids 6197699 view list period_days 100 base_url /dotlrn/calendar/} }}
In my case it does not show the appropriate calender items?
Even it I use
{{adp /packages/calendar/www/mini-calendar {view day base_url /dotlrn/calendar/} }},
it shows a calendar in monthly view with no lines (css) in place.
What am I doing wrong?