Which version of Firefox are you using? This was a problem in some beta versions of Firefox 4 for Android, but it should be fixed in the latest version (Firefox 4.0.1) from the Android Market.

fennec-4.0b2.multi.eabi-arm

That is an old version. To get the fix for this bug, search in the Android Market or go to http://firefox.com/mobile/download/

You will need to uninstall Firefox 4.0b2 before installing the latest version. This will erase your Firefox bookmarks and settings, sorry. (This is because of a one-time change we made after 4.0 beta 2 was released. You will not need to uninstall or reset your settings for any future upgrades.)

in http://firefox.com/mobile/download/ . error : "There are no Android phones associated with this account. Please sign in with a different account." signing in with google acount. thanks

https://wiki.mozilla.org/Mobile/Platforms/Android lists some other ways to download Firefox for Android if the Market web page does not work for you.

thanks a lot.

you must download browser that support farsi language , then check persian language site same as : http://www.kamnazir.com