I just got eclipse and a plug-in named PHPeclipse. I set up the debugger and when I ran phpinfo(), I saw the: "DBG php debugger, version 2.11.32, Copyright 2001, 2005, Dmitri Dmitrienko, www.nusphere.com". So I guess it is installed correctly. But everytime I try to launch a debug session, I get a

ava.net.SocketException: socket closed
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.PlainSocketImpl.accept(Unknown Source)
at java.net.ServerSocket.implAccept(Unknown Source)
at java.net.ServerSocket.accept(Unknown Source)
at net.sourceforge.phpdt.internal.debug.core.PHPDBGProxy$PHPLoop.run(PHPDBGProxy.java:395)

error. Has anyone else ever seen this? What can I do to get my debugger working?

PHPEclipse has its own DBG client. So make sure you do not run DbgListener.exe and TCP/7869 socket is not in use by other applications.
If it does not help, please contact phpeclipse authors/maintainers to find a solution or workaround.

If your PHP-installation is in C:\PHP make sure you set this path in
"PHPEclipse/PHP/Installed Interpreters" and check it.