Try 'hp-setup --disable-dbus' -- does that work around it?

Oh, wait, that's an hp-toolbox option...

An update of the situation is

1) it works when I run "hp-setup -i"

2) I've run strace and this is the last part of it

stat64("/root/.kde/share/config/kdeglobals", {st_mode=S_IFREG|0600, st_size=117, ...}) = 0
stat64("/root/.kde/share/config/kdeglobals", {st_mode=S_IFREG|0600, st_size=117, ...}) = 0
stat64("/root/.kde/share/config/kdeglobals", {st_mode=S_IFREG|0600, st_size=117, ...}) = 0
fstat64(8, {st_mode=S_IFREG|0600, st_size=117, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7c26000
read(8, "[$Version]\nupdate_info=kwin.upd:k"..., 4096) = 117
read(8, ""..., 4096) = 0
close(8) = 0
munmap(0xb7c26000, 4096) = 0
stat64("/root/.kde/share/config/oxygenrc", 0xbf9345b4) = -1 ENOENT (No such file or directory)
stat64("/etc/kde/oxygenrc", 0xbf9345b4) = -1 ENOENT (No such file or directory)
stat64("/usr/share/kde-settings/kde-profile/default/share/config/oxygenrc", 0xbf9345b4) = -1 ENOENT (No such file or directory)
stat64("/usr/share/config/oxygenrc", 0xbf9345b4) = -1 ENOENT (No such file or directory)
socket(PF_FILE, SOCK_STREAM, 0) = 8
connect(8, {sa_family=AF_FILE, path=@"/tmp/dbus-YMPFCiHxV1"...}, 23) = 0
fcntl64(8, F_GETFL) = 0x2 (flags O_RDWR)
fcntl64(8, F_SETFL, O_RDWR|O_NONBLOCK) = 0
fcntl64(8, F_GETFD) = 0
fcntl64(8, F_SETFD, FD_CLOEXEC) = 0
geteuid32() = 0
rt_sigaction(SIGPIPE, {0x1, [PIPE], SA_RESTART}, {0x1, [], 0}, 8) = 0
poll([{fd=8, events=POLLOUT}], 1, 0) = 1 ([{fd=8, revents=POLLOUT}])
write(8, "\0"..., 1) = 1
write(8, "AUTH EXTERNAL 30\r\n"..., 18) = 18
poll([{fd=8, events=POLLIN}], 1, -1) = 1 ([{fd=8, revents=POLLIN}])
read(8, "OK a16eba9acfc3638eec7139ec4a60df"..., 2048) = 37
poll([{fd=8, events=POLLOUT}], 1, -1) = 1 ([{fd=8, revents=POLLOUT}])
write(8, "BEGIN\r\n"..., 7) = 7
poll([{fd=8, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=8, revents=POLLIN|POLLOUT|POLLHUP}])
read(8, ""..., 2048) = 0
close(8) = 0
futex(0x98c4114, FUTEX_WAIT_PRIVATE, 1, NULL <unfinished ...>

... nothing more is added after that

3) I've used the python debugger and found that it hangs on a call to
QApplication(sys.argv)

> /usr/share/hplip/setup.py(193)<module>()
-> log.debug("param=%s" % param)
(Pdb)
> /usr/share/hplip/setup.py(196)<module>()
-> if mode == GUI_MODE:
(Pdb)
> /usr/share/hplip/setup.py(197)<module>()
-> if ui_toolkit == 'qt3':
(Pdb)
> /usr/share/hplip/setup.py(202)<module>()
-> if not utils.canEnterGUIMode4():
(Pdb)
> /usr/share/hplip/setup.py(206)<module>()
-> if mode == GUI_MODE:
(Pdb)
> /usr/share/hplip/setup.py(207)<module>()
-> if ui_toolkit == 'qt3':
(Pdb)
> /usr/share/hplip/setup.py(280)<module>()
-> try:
(Pdb)
> /usr/share/hplip/setup.py(281)<module>()
-> from PyQt4.QtGui import QApplication, QMessageBox
(Pdb)
> /usr/share/hplip/setup.py(282)<module>()
-> from ui4.setupdialog import SetupDialog
(Pdb)
 /usr/share/hplip/setup.py(287)<module>()
-> app = QApplication(sys.argv)
(Pdb)

... hangs

4) but, if I run it via the hp-toolbox (Device, Setup device), it always works.

5) on my PS3 it always works

I don't really know who to blame here...

Me either. :-(

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