Just to let you know that there is a problem with the instructions
on your web page at: http://www.pgadmin.org/download/ubuntu.php
1. Ubuntu 7.10 (Gutsy) does not have 'deb' so the line:
deb [MIRROR URL]/pgadmin3/release/ubuntu gutsy pgadmin
produces:
bash: deb: command not found
2. Looking at my local mirror site
(http://ftp2.uk.postgresql.org/sites/ftp.postgresql.org/pgadmin3/release/ubuntu/dists/gutsy/)
it appears that only i386 is available (no AMD64).
Regards
John