Firefox 3.5.1 (Shiretoko) fails to launch in Arch Linux

Abstract: Firefox 3.5.1 needs libjpeg.

After updating my Firefox (Shiretoki) to version 3.5.1 in Arch Linux, I cannot launch it. When I tried to start it from command line, it says:

$ firefox
Coundn't load XPCOM
$ 

Then I tried to run xulrunner directly, I got a Error message saying that libjpeg cannot be found. So I installed libjpeg-7-1, and Firefox is back again. Hopefully the Arch people can add libjpeg to Firefox's dependency.