i have the same problem, i think.
here is output from eclipse log:
!ENTRY com.sun.enterprise.jst.server.sunappsrv 1 1 2008-11-10 20:10:50.484
!MESSAGE GlassFish: in SUN SunAppServerLaunch launch
!ENTRY com.sun.enterprise.jst.server.sunappsrv 1 1 2008-11-10 20:10:50.500
!MESSAGE GlassFish: in SUN SunAppServerLaunch Forcing a STOP!!!!
!ENTRY com.sun.enterprise.jst.server.sunappsrv 1 1 2008-11-10 20:10:52.515
!MESSAGE GlassFish: done executing: false __locations
!ENTRY com.sun.enterprise.jst.server.sunappsrv 1 1 2008-11-10 20:10:52.515
!MESSAGE GlassFish: apparently CREDENTIAL_ERROR
!ENTRY com.sun.enterprise.jst.server.sunappsrv 4 150 2008-11-10 20:10:52.515
!MESSAGE Port conflict: Please stop the server process using the same port as the one used by the Application Server.
!STACK 0
java.lang.RuntimeException: A server process is already running on this port but we cannot determined if it's a GlassFish process (lack of info or credentials)
at com.sun.enterprise.jst.server.sunappsrv.SunAppServerLaunch.launch(SunAppServerLaunch.java:126)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:764)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:614)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:607)
at org.eclipse.wst.server.core.internal.Server.startImpl2(Server.java:2771)
at org.eclipse.wst.server.core.internal.Server.startImpl(Server.java:2721)
at org.eclipse.wst.server.core.internal.Server$StartJob.run(Server.java:306)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
Slavo
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