There are few differences in Rhel and Solaris apachectl

Specifying installation
Rhel

OPTIONS="-f /opt/jbcs-httpd24-2.4/httpd/conf/httpd.conf -E /opt/jbcs-httpd24-2.4/httpd/logs/httpd.log"
$HTTPD $OPTIONS -k $ARGV

Solaris

ROOTDIR="-d /opt/jbcs2/jbcs-httpd24-2.4/etc/httpd"
$HTTPD $ROOTDIR $OPTIONS -k $ARGV

If one use apachectl as specified in apache documentation (./apachectl start/stop/restart/...) then he have no real problem, just curiosity

ConfigTest

configtest)
    testconfig
;;
function testconfig() {
# httpd is denied terminal access in SELinux, so run in the
# current context to get stdout from $HTTPD -t.
if test -x /usr/sbin/selinuxenabled && /usr/sbin/selinuxenabled; then
  runcon -- `id -Z` $HTTPD $OPTIONS -t
else
  $HTTPD $OPTIONS -t
fi
ERROR=$?
}

Solaris

configtest)
    $HTTPD -t
    ERROR=$?
    ;;

Issue If httpd is installed in non standard location ( != /opt) then config test will not work or will start at another installation (located in /opt)
Rhel use $OPTIONS to specifying installation

Other option
Rhel

*)
    $HTTPD $OPTIONS "$@"
    ERROR=$?

Solaris

*)
    $HTTPD "$@"
    ERROR=$?

./apachectl -V

Will fail on solaris as one must specify location (-d, -f), Rhel works fine

Rhel use $OPTION to specify installation location when starting with old (-k start), but solaris don't do it... Documentation isn't very specific about what is right.
Issue

./apachectl -k start -d /opt/yolo

should fail, but it starts as it starts with $OPTIONS that is probably more powerful than -d
Solaris correctly fails