Had the same problem when installing ubuntu-xen-desktop.
Unpacking xen-utils-3.1 (from .../xen-utils-3.1_3.1.0-0ubuntu15_i386.deb) ...
dpkg: error processing /var/cache/apt/archives/xen-utils-3.1_3.1.0-0ubuntu15_i386.deb (--unpack):
trying to overwrite `/usr/sbin/xentrace_setmask', which is also in package xen-utils-common
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Errors were encountered while processing:
/var/cache/apt/archives/xen-utils-3.1_3.1.0-0ubuntu15_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
root@PoivreEtCell:~#
Had the same problem when installing ubuntu-xen-desktop.
Unpacking xen-utils-3.1 (from .../xen- utils-3. 1_3.1.0- 0ubuntu15_ i386.deb) ... apt/archives/ xen-utils- 3.1_3.1. 0-0ubuntu15_ i386.deb (--unpack): xentrace_ setmask' , which is also in package xen-utils-common apt/archives/ xen-utils- 3.1_3.1. 0-0ubuntu15_ i386.deb ll:~#
dpkg: error processing /var/cache/
trying to overwrite `/usr/sbin/
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Errors were encountered while processing:
/var/cache/
E: Sub-process /usr/bin/dpkg returned an error code (1)
root@PoivreEtCe