I get the same errors. I've observed the startup of Apache using 'top'. I can see two instances of httpd starting. Then after a few seconds, they die. When they die, these errors are written to the /var/log/httpd/error_log file:
dyld: /usr/sbin/httpd Undefined symbols:
I also noticed (in top) two other processes, "c++flt3" and "crashdump" spawning and then dying while the httpds die.
Also, am I supposed to uncomment the "LoadModule dav_module libexec/httpd/libdav.so" and "AddModule mod_dav.c" directives in the httpd.conf file?
If I leave these commented out, I immediately get a "Mis-spelled" error on the command DavLockDB.