Hi,
I use Droidxxxx.ttf fonts which support Thai from other Android mobile phone to replace the builtin Droidxxxx font. These are Droid font files in Nook which you have to replace:
DroidSans-Bold.ttf
DroidSans.ttf
DroidSansFallback.ttf
DroidSansMono.ttf
DroidSerif-Bold.ttf
DroidSerif-BoldItalic.ttf
DroidSerif-Italic.ttf
DroidSerif-Regular.ttf
Read more:
http://nookdevs.com/Font_Changes#Fonts_on_the_Nook
After doing this, I can read Thai website and RSS feeds. However, you must have softrooted you Nook before doing this; and find same Droidxxxx.ttf files which have same filenames in other Arabic supported Android phone.