Why? Note this:
Example of usage:
From Symbian OS v9 the default location for system font file installation changed to \resource\fonts\ (on any drive). The phone still needs to be rebooted in order for the font file to be automatically loaded. Note that the \resource folder is protected by the TCB capability, which means that to install the file it must be bundled in a SISX file; there is no requirement for this SISX file to be signed, unless the phone itself mandates that only signed SISX files may be installed.