servers

Hello,
Is there any limit to the number of linked servers i can add via EM?. where can i find more info on adding/configuring linked servers in MSSQL2k and the limitations/drawbacks if any?
Thanks in advance..one limitation of linked servers I discovered recently is that loopback scenarios are not supported by MS, even though they often work. what I mean by loopback is a LS that points to itself.

One case I know that is broken in a loopback scenario is this:

INSERT INTO localtable EXEC LoopbackLinkedServer.dbo.RemoteSproc

as is detailed here:

http://forums.microsoft.com/MSDN/ShowPost.aspx?postid=124137&siteid=1

Linked servers are very useful. why couldn't MS get the obvious use case of loopback to work? :(

I should note that the case above is broken on 2005. it may work on 2000, I haven't tried it.