figured it out.
you can stop mavericks putting web sites on the ip address you have filemaker on. in fact, you can shift all the mavericks sites real easy...
in
/Library/Server/Web/Config/apache2/sites
there are several files:
0000_any_443_.conf
0000_any_80_.conf
each of these files has a line which tells which ip addresses to listen on:
<VirtualHost *:80 >
change this to whatever you want mavericks server to be running the web pages on (eg
VirtualHost <newIP>:<newport>
and
VirtualHost <newIP>:<newsecureport>
or whatgever you need. (shifting to *:81 and *:444, perhpas?, or to a secondary IP address)
then in
virtual_host_global.conf are a few more details change these too:
sudo more /Library/Server/Web/Config/apache2/sites/virtual_host_global.conf.default
# This file is auto-generated by the Server application's
# configuration mechanism whenever settings are saved.
# The Listen and NameVirtualHost directives are generated
# based on the VirtualHost directive inside
# each site configuration file found in this directory.
Listen *:443
NameVirtualHost *:443
Listen *:80
NameVirtualHost *:80
so change these to
Listen <newIP>:<newport>
NameVirtualHost <newIP>:<newsecureport>
Listen <newIP>:<newport>
NameVirtualHost <newIP>:<newport>
mavericks stops listening to all ip addresses ont he standard ports 80 and port 443 now, leaving them clear for filemaker