It is still a nightmare for people who're using Linux distros other than Fedora to view indic on Firefox for Linux. Thats not the only problem now...
For the CSS properties:

• text-align:justify
• "letter-spacing"
• "word-spacing"

indic gets scattered and looks odd.

See the screenshots: screenshot1 (kannada), screenshot 2 - tamil.

I had observed this issue when doing a template changeover for wordpress 1.5 for myself weeks back. Today, I searched around to see if there's a bug filed on it and found this one. A bleak thing on my favourite browser :( I might check out mozilla CVS this week to try and track the bug if possible.
But the irony is that, for the last few times I tried to build mozilla, I've had very little success ;) (I tried for a build with pango support to enable indic last week). Maybe weekend's the best time and hope I'll get it this time over :)