The trouble is, while PL/SQL procedures do generate HTML, I cannot make image folder work. That is, when I try to insert an IMG tag, it shows that it can't find that file in /xxx/img folder.
I tried to redefine DocumentRoot in httpd.conf - it works only on that folder itself, not recursively. I tried to change DOCUMENT_ROOT in dads.conf - it doesn't work at all.
So the question is, how can I make images deep inside that root folder show up?
At last I have found an answer and a reason of this behavior.
The reason is Oracle's hand-made handler, pls_handler, used for any DADs, made up as Apache Locations.
Trying to create folders for storing images like $ORACLE_HOME/htdocs/myapp/img, I interfered with that directive:
<Location /myapp>
SetHandler pls_handler
# lots of stuff
</Location>
And thus, anything under $ORACLE_HOME/htdocs/myapp folder was processed as PL/SQL procedures.