Maybe you did not notice, but the latest development version of Drupal comes with RTL language support. Unfortunately it does not go as far as I would like it to be, but Drupal now knows about RTL languages and hand this information out to the theme too. No core theme ships with proper RTL support yet (none of them set the direction on the HTML tag, neither they ship with RTL CSS). I (as one of the guys being instrumental in getting this extended language support into Drupal core) think that the core themes should have support for RTL languages too, as it does not seem to be a huge undertaking, if it is done by people who know what they are doing. This is why I am here to post this notice.
There is an existing issue here which deals with adding RTL CSS into core: http://drupal.org/node/110418
Comments
New patches nees reviews
Hello all,
We have prepared two patches that concern RTL communities, such as this group, or other communities in arabic speaking countries:
1. Changing drupal_add_css function to include RTL styles as well: http://drupal.org/node/145737
2. A modified core theme - http://drupal.org/node/147265
Please review the patches, and add some more RTL core themes, or contrib themes.
Drupal 6 will be RTL compliant, but only as an infrastructure. We still have issues to deal with:
1. modifying page.tpl.php or relating to it in a way that doesn't force us to change it
2. adding more core themes, so Drupal can be an out-of-the-box bi-directional CMS
3. maybe the hardest - "educating" themers and module developers to supply RTL styles
education
It would be nice if you could collect the conversion rules to follow when doing an LTR to RTL conversion, so others can do it and validate your changes. This could go to the themers handbook, so it is accessible to everyone.