I was working on this on webOS 1.4.5 and I stopped after reaching a deadend.
The problem is that the webcore in 1.4.5 for some reason didn't show arabic glyphs. It shows them as blank. Therefore, even if you installed arabic font they don't show; however, you can see that native application display the glyphs just fine. As a result, I came to the conclusion that webcore, as it is used to display everything like SMS, calendar and so on, is somehow either outdated or modified.
Of course, the fact that it doesn't display a set of glyphs gives out the fact that it was modified from Palm. I looked for the code but there were some parts not included; therefore, I just dropped the subject.
However, now I can resume working as I can see a sight of relief. You can clearly see that the glyphs are recognized. Now, implementing a function that will process the string before displaying it to connect the glyphs.