In RedHat 6.1, the default KDE login window shows a dialog box with a space to
type in the user name, one in which to type the user password, and a drop down
list to select the window manager/desktop environment of choice. By making the
following changes to /usr/share/config/kdmrc, user icons will appear in
the top of the login box.
Here is what the default lines that control user icon view in kdmrc look like (other
lines between these two are not shown, and are represented by "..."):
#Users=root;johndoe
...
UserView=false
Here are the same lines after editing; delete the comment character ("#") in front of "Users=..." and change "johndoe" to your username (if there are more user accounts on your system, you may add their usernames here, separated by semi-colons as shown). Change "UserView=false" to "UserView=true" as shown here:
Users=root;johnpipe
...
UserView=true
Now, when you login, you may click on an icon with the mouse to enter the user name; you must still type in your password.
You can add your own icons in place of the default icons; place you own icons in /usr/share/apps/kdm/pics/users/. They should be of size 64 x 64, according to the kdm handbook; in KDE 1.x, the default icons are 62 x 63, and my new user icon is 60 x 60, so if icons are reasonably close to the specified 64 x 64 size, they will work OK. The handbook says "kdm is able to handle icons of different sizes, but the result looks messy.", so there is evidently some leeway here. Your icons should be named 'username.xpm', for example my username is "johnpipe" and my new icon is named 'johnpipe.xpm'
NOTE: at some time since kde 1.x, the icon format has been changed from '.xpm' (XPixMap) to '.png' (portable network graphic).