I get this on a dual P4 running debian squeeze:
$ sudo dpkg -i Pd-0.44.0-extended-20131003-debian-squeeze-i386.deb
dpkg: error processing Pd-0.44.0-extended-20131003-debian-squeeze-i386.deb (--install):
package architecture (amd64) does not match system (i386)
Errors were encountered while processing:
Pd-0.44.0-extended-20131003-debian-squeeze-i386.deb
Martin