Then you can use a file manager tool to explore your system files. Make sure your file manager has gotten root permission. You can check apps' root permission using Superuser permissions app (This is a part of the UniversalAndroot app and will be installed automatically when you install UniversalAndroot app).
I used this tool called Root explorer (Get it from here). First you have to mount the file system allowing Read/Write operations. You can simply do this by tapping this "Mount R/W" button.
Grant read/write permission to /system/fonts folder.
Then you have to rename or backup your existing DroidSansFallback.ttf in /system/fonts and copy this new DroidSansFallback.ttf (Get it from here) to /system/fonts. Now you are done. See! That was very easy! Not as easy as installing on Sony Ericsson A200 platform though :D
I believe the author of the above (right) facebook status wouldn't mind me using it :P