thanks for your interestment.no, i don't need to use a proxy, so i do not understand why i have to configure my network connection, because otherwise works great.also i don't know how to have the output of system trace.
this is system info dialog:
OS
CPU: i686
System: Linux
Release: 2.6.31-21-generic
Version: #59-Ubuntu SMP Wed Mar 24 07:28:56 UTC 2010
Qt version 4.4.3
Username
root
Attached USB devices
VID: 046d PID: 0896, OEM Camera
VID: 046d PID: c030, Logitech Inc. iFeel Mouse
VID: 0781 PID: 7421, SanDisk Sansa e280
VID: 1d6b PID: 0001, Linux 2.6.31-21-generic uhci_hcd UHCI Host Controller
VID: 1d6b PID: 0002, Linux 2.6.31-21-generic ehci_hcd EHCI Host Controller
Filesystem
/, 49922 MiB available
/proc, 0 MiB available
/sys, 0 MiB available
/sys/fs/fuse/connections, 0 MiB available
/sys/kernel/debug, 0 MiB available
/sys/kernel/security, 0 MiB available
/dev, 496 MiB available
/dev/pts, 0 MiB available
/dev/shm, 496 MiB available
/var/run, 496 MiB available
/var/lock, 496 MiB available
/lib/init/rw, 496 MiB available
/proc/sys/fs/binfmt_misc, 0 MiB available
/home/franzisk/.gvfs, 0 MiB available
/media/Sansa e280, 4119 MiB available