"appletviewer.main.warn.cantreadprops" is not in MsgAppletViewer.java.
But "appletviewer.main.warning.cantreadprops" is in the file for same meaning.

Tested by Kestrel "J" build
In case that both of .hotjava/properties and .appletviewer do not exist in
user's home directory, MissingResourceException for "appletviewer.main.warn.cantreadprops" occurs and appletviewer does not work.