GNU Parted Error: Unable to satisfy all constraints on the partition.

[Piero Finizio]

GNU Parted version 1.8.7
Assertion (!disk->update_mode) at disk.c:419 in function
ped_disk_destroy() failed.
Error: Unable to satisfy all constraints on the partition.
Backtrace has 20 calls on stack:
  20: /usr/lib/libparted-1.8.so.7(ped_assert+0x3b) [0xb759c56b]
  19: /usr/lib/libparted-1.8.so.7(ped_disk_destroy+0x94) [0xb75a2034]
  18: /usr/lib/libparted-1.8.so.7(ped_disk_duplicate+0x1e8) [0xb75a4908]
  17: qtparted [0x806eb1c]
  16: qtparted [0x806ac09]
  15: qtparted [0x8072790]
  14: qtparted [0x80733f7]
  13: qtparted [0x808ae0b]
  12: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x16d)
[0xb7b638ad]
  11: qtparted [0x808e07d]
  10: qtparted [0x808e0d1]
  9: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x129)
[0xb7b63869]
  8: qtparted [0x8092d0d]
  7: qtparted [0x8062f33]
  6: qtparted [0x8092e8f]
  5: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x16d)
[0xb7b638ad]
  4: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN9QListView16selectionChangedEP13QListViewItem+0x91)
[0xb7eaacc1]
  3: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN9QListView14setCurrentItemEP13QListViewItem+0x22b)
[0xb7c4392b]
  2: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN9QListView25contentsMousePressEventExEP11QMouseEvent+0x336)
[0xb7c46806]
  1: 
/usr/lib/qt3/lib/libqt-mt.so.3(_ZN9QListView23contentsMousePressEventEP11QMouseEvent+0x24)
[0xb7c471b4]

Greetings,
                                                             Piero Finizio