I've noticed that renamed contacts doesn't stay renamed when the contact renames itself. Is it possible to change this behaviour so that the name I've given a contact always stays to that name?

ie:
1. My contact John Doe has a display name of: "JoooOoooooohn".
2. I rename him with Plus! to "John Doe"
3. He renames himself in his MSN to: "I'm really annoying and changes my display name all the time so that ppl can't find me in their address lists"
4. The display name in my MSN gets updated, even though I've renamed him :/

what MsgPLus Version do you have? 

v.3.61.145

Noone more than me that's experiencing this?

For me it doesn't matter which version, it has always been like this. Can mention that I also use an A-patched version of MSN.

could be, i have searched without any other same problems like this so it could be only you, ,

Yeah...

Since custom name feature was introduced, I've never heard a problem like that.

Try to reinstall MSN Messenger and don't patch it, or maybe use different patch.
See if your contact can rename himself.

I once encountered a problem, but it was related to Stuffplug and it was in convo windows.
My problem was the chat only name overrides the costum name feature.
I don't know if it has been fixed or not.

Really strange, cause it happens with both the English and Swedish version of MSN, on two different computers.

Click Contacts > Manage Contacts > View Contacts By > Email Address

See if the custom name stays enabled.

@Matty, it is already at this setting.

When you set the name try using John Doe - (!N) and see what happens then.