Over deze add-on
Usage: Click "Add to Firefox". A confirmation window will appear. Click "Install now". Then the dictionary will be installed automatically. Restart FireFox. Then type Bangla text in text box or input box (such as mail compose, blogging, etc). Right click on the text box and select Language->Bangla / Bangladesh. Now it will underline the wrong spelled words. Enjoy....and please write some comments about it.