root@ubuntu:~/freenx# ls
nxclient_2.1.0-17_i386.deb  nxserver_2.1.0-22_i386.deb
nxnode_2.1.0-22_i386.deb
root@ubuntu:~/freenx# dpkg -r nxclient_2.1.0-17_i386.deb
dpkg: you must specify packages by their own names, not by quoting the names of the files they come in

Type dpkg --help for help about installing and deinstalling packages [*];
Use `dselect' or `aptitude' for user-friendly package management;
Type dpkg -Dhelp for a list of dpkg debug flag values;
Type dpkg --force-help for a list of forcing options;
Type dpkg-deb --help for help about manipulating *.deb files;
Type dpkg --license for copyright license and lack of warranty (GNU GPL) [*].

Options marked [*] produce a lot of output - pipe it through `less' or `more' !
root@ubuntu:~/freenx# dpkg -r nxclient
dpkg: dependency problems prevent removal of nxclient:
 nxnode depends on nxclient (>= 2.1.0).
 nxserver depends on nxclient (>= 2.1.0).
dpkg: error processing nxclient (--remove):
 dependency problems - not removing
Errors were encountered while processing:
 nxclient
root@ubuntu:~/freenx#