As requested here is the 64bit version of the ubuntu 9 template that runs on citrix xenserver paravirtualised.
download link
http://rapidshare.com/files/289417026/Ubuntux64.7z.001
http://rapidshare.com/files/289470456/Ubuntux64.7z.002
Unzip files with 7zip
user name root
pass: password
the image is set as dhcp, has xen virtualised pv kernel and xenserver tools installed.
Just import trough xencenter or the xe client, and your ubuntu is ready…
Isaac