rpaf-2.0_module замените на mod_rpaf.
Это "фича" apxs.
Starting httpd2 (prefork) httpd2-prefork: Syntax error on line 116 of
/etc/apache2/httpd.conf: Syntax error on line 30 of
/etc/apache2/sysconfig.d/loadmodule.conf: Can't locate API module
structure `rpaf-2.0_module' in file
/usr/lib64/apache2-prefork/mod_rpaf-2.0.so:
/usr/lib64/apache2-prefork/mod_rpaf-2.0.so: undefined symbol:
rpaf-2.0_module
