With Tiger's Terminal, Apple fixed the issue that makes two windows open when opening a telnet:// URL. I also noticed that the ssh:// URL is also supported from Safari. So, you can create a folder in your Safari's bookmark bar that will contain all your favorites ssh:// and telnet:// URLs. You can also insert your username inside the URL:
ssh://myuser@myserver.mycompanie.com
Fast access to your favorite servers from Safari...
Mac OS X Hints
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