The Virtual Disk Migration Utility 1.0 is a V2V tool to convert VMware and Microsoft Virtual Server/Virtual PC virtual machines (with Microsoft Windows Virtual Machines installed) to the Xen Virtual Appliance (XVA) format.

According to the README file:

The Virtual Disk Migration Utility converts Windows virtual machines installed on VMware and Microsoft Virtual Server (MSVS) or Virtual PC to Xen Virtual Appliance (XVA) format.  The resulting XVA can then be imported into a XenServer Family product (XenEnterprise, XenServer or XenExpress) and booted as a XenServer HVM guest.  The XVA format output directory contains:

i)  For each virtual disk, a directory containing gzip-compressed chunks of the virtual disk.  Each chunk contains up to 1GB (1e9 bytes) of data.
ii) A file named ova.xml that contains configuration settings (for example, memory size and number of vCPUs).

This tool relies heavily on the VDK utility (http://chitchat.at.infoseek.co.jp/VMware/vdk.html) which in turn was made possible by the FileDisk utility (http://www.acc.umu.se/~bosse).  Xensource has modified and added routines to the VDK utility for the conversion to XVA to be made possible.  Also, to produce the gzip-compressed chunks of the virtual disk in XVA format, the Win32 zlib library is used (http://www.zlib.net).

You can download it, here.