Use your favorite "real" text editor... Possible options include:

• vi (which comes installed)
• Vim (vi clone/enhanced)
• emacs
• nano (pico clone/enhanced)
• joe (plainly the best, as I use it!)
• leafpad (probably the friendliest choice, as it's gtk+/hildonized)

The Nokia apps, and some third-party apps, see only the ~/MyDocs/ tree. Since the file you need to edit lies outside that tree, you can't use e.g. notes, without excess trouble (like making a symlink up to the ~/.mozilla directory). You'll need to go to xterm, and doFor the other file, you will probably need to be root to access it...