There has been a large group of Sony Ericsson Xperia X10 users that have managed to get by up until now by not having their native language support by the handset. In fact, in the run up to the Android 2.1 update, the demand for Arabic fonts in the Xperia X10 intensified. Whilst, the phone still does not support the fonts out of the box, there is finally a workaround for those using a rooted handset with the latest update.
medo18 from xda-developers has the fonts available to download (taken from another device) and some detailed instructions on how to get your X10 updated. Given the ease with which the Arabic fonts are implemented, it does make me wonder why Sony Ericsson, a supposedly global brand, couldn’t provide the fonts within the default firmware. You can check out the full instructions here.
Update: If you want to go that one step extra, and get deep system Arabic language support, then check out ce4arab where there are detailed steps to get this working. Thanks Khaled!