Description of problem:
The init script for dnsmasq is not aware of the possibility to have several dnsmasq processes on the same system.
Now, you have for example libvirt installed with its dnsmasq embedded processes and you also want to use dnsmasq inside the OS, you cannot easily manage this.
For example if you have cobbler server on the same system where you have libvirt configured (qemu/KVM host with several networks), each time you issue the command "cobbler sync" you get all the dnsmasq processes killed and then only the OS one restarted... 
And also, to restart libvirtd embedded dnsmasq processes is very difficult (it seems service libvirtd restart doesn't make it...)

Version-Release number of selected component (if applicable):
dnsmasq-2.46-2.fc11.x86_64

How reproducible:
always

Steps to Reproduce:
1. install and configure libvirt and some virtual networks with virt-manager tool
2. configure dnsmasq for other purposes too (cobbler server in my case)
3. service dnsmasq restart
  
Actual results:
all the dnsmasq processed are killed

Expected results:
only the OS managed one dnsmasq process should be impacted by the several commands

Additional info:

With simple changes, where instead of killproc function, I use "killproc -p" (suc as into the httpd init script) I get what expected.
Probably my changes are not perfect but a simple start to accomodate what needed.

I'm not a coder, but I'm going to attach a diff between my dnsmasq and the one provided. 

Now, applying the patch, on my system I get:
nobody    2648     1  0 Jul17 ?        00:00:00 /usr/sbin/dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/intracluster.pid --conf-file=  --listen-address 172.16.0.1 --except-interface lo --dhcp-range 172.24.0.101,172.31.255.254
nobody    2718     1  0 Jul17 ?        00:00:00 /usr/sbin/dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/default.pid --conf-file=  --listen-address 192.168.122.1 --except-interface lo --dhcp-range 192.168.122.2,192.168.122.100
nobody    2733     1  0 Jul17 ?        00:00:01 /usr/sbin/dnsmasq -s mydomain.it

[root@virtfed storage]# cobbler sync
/usr/lib64/python2.6/site-packages/Cheetah/CacheRegion.py:30: DeprecationWarning: the md5 module is deprecated; use hashlib instead
  import md5
Shutting down dnsmasq:                                     [  OK  ]
Starting dnsmasq:                                          [  OK  ]
[root@virtfed storage]# ps -ef|grep dnsmasq
nobody    2648     1  0 Jul17 ?        00:00:00 /usr/sbin/dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/intracluster.pid --conf-file=  --listen-address 172.16.0.1 --except-interface lo --dhcp-range 172.24.0.101,172.31.255.254
nobody    2718     1  0 Jul17 ?        00:00:00 /usr/sbin/dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/default.pid --conf-file=  --listen-address 192.168.122.1 --except-interface lo --dhcp-range 192.168.122.2,192.168.122.100
nobody    7755     1  0 11:03 ?        00:00:00 /usr/sbin/dnsmasq -s mydomain.it

Thanks for your attention.
Gianluca