Hello Gustaf,
again many thanks for your invaluable help.
You are absolutely right! The problem is due to an use flag set by defult in Gentoo.
https://packages.gentoo.org/useflags/bindist
I've reemerged openssl with this flag unset and I could compile and install naviserver!!
I'm facing now some other problems when running it, that I guess are minor.
Extracts from my error log say:
[xxxxxx...xxxxx] Error: pidfile: failed to open pid file 'nsd.pid': Permission denied
I've created a blank pid file under logs and changed its owner to the non-root user under which I run nsd.
[xxxxxx...xxxxx] Warning: modload: could not load /usr/local/ns/bin/nscp.so: /usr/local/ns/bin/nscp.so: undefined symbol: Ns_ConfigCreateSection
I'd be very grateful for any hint regarding this error and warning.
Best,
Michael