Hello,
Please execute the below steps
1. Un-install jre/jdk 1.6 from the client (Where you see rectangular boxes instead of Khmer characters)
2. Download and install JRE from
http://www.4shared.com/file/iusrZNt7/jre-6u13-windows-i586-p.html3. Copy the font.properties into the lib directory as you did earlier
4. Also I hope you installed KhmerOS Unicode font
Let us know if this worked.