finally, I managed to repair the feed plugin. Actually, [NiKO] in the channel #dokuwiki in Freenode pointed me to the right patch:
UPDATE: well, obviously the feed component still has problems with <code> blocks. Well, it seem that I'll have to be more careful in future, or fix that part of the feed component as well. Patch available here
UPDATE2: ok, now the code blocks should be working too. I've cleaned the dokuwiki cache, so I will spam aggregators like http://planet.lusc.de, and other feedreaders. I apologise for that.
~~DISCUSSION~~
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