I am currently testing Tamil language pack in a demo site of mine. The Menus and Headings are still showing in English. However, your hindi pack demo site's menus and headings are in hindi. Did I missed anything?
Yes, that is true. In IndicJoomla! distribution, along with the language, I also did some work on joomla.sql file such that it insert menu, categories and so on in HIndi. Once the language file is done, Log into the backend and start changing stuff there. Once its done, take a back up of the SQL. I then edited this SQL such that it can be used in the installation too. If I remember correctly, I changed the database to #__ and that was it...
For example, say if your database name is "demo". When you take a back up of this database, the SQLs will look something like
insert into demo_weblinks ......and so on
I change this into
insert into #__weblinks
I hope this makes sense...
This also answers your secong questions
I want to change the Days & Months showed also in Tamil, is there any way?
In your /includes/joomla.php you will need to hardcode this. Please see a function called mosFormatDate in IndicJoomla distribution for more details.
In PDF display the tamil characters are not displaying properly. I need to work on this. Any suggestion?
As of Joomla 1.0.7, PDF does not work for Indic Languages. I have it disabled in IndicJoomla distribution. It will be supported in Joomla 1.1
I hope this helps