Yes it does. The fact that you don't seem to be able to implement your own is probably based on a common, but simple error
When adding servers/networks to your own servers.ini file follow the following steps. (Note: I've included all steps, but you probably already know some (if not all) of them.)
1) Open mIRC options using Alt+o
2) Select Connect
3) If there is a + beside Connect, click the +
4) Select Servers
5) Click Add
6) Fill in the dialog that opens, INCLUDING the GROUP entry
The GROUP entry is what allows the new server to be easily found in the servers file (aka servers.ini)
This is the most common item that people don't enter, and then wonder why the new entry isn't showing.
My preference is to use the Network Name.
7) Click Add
8) Repeat steps 5-7 for each new server (even if there's more than one server for each network)
9) Click OK
