I'm using the WebKit nightly r37056 both in a i686 linux PC and in an armv4t mobile (Openmoko Freerunner). I've tried to connect to Facebook (both using iphone.facebook.com and facebook.com); while in the i686 PC I was able to login and connect, using the armv4t mobile when I click on "Login" the "load-committed" signal is emitted, but I get no progress at all. I can wait minutes, but nothing happens. I've made the tests in the two environments above, both using the default GtkLauncher test browser and using Midori, so I figure that the problem resides in libwebkit itself (and it seems related to javascript, looking to the login form). I've tested also an r30762 build (older, but built by OpenEmbedded) in the arm device, but the same happens.
I've made some more tests and using Debian armel webkit library I'm able to login. So, I've re-used my precompiled webkit library using the other debian armel libraries (forcing to use them with the LD_* environments vars) and I was able to login. So, the problem seem to stay in libcurl or libgutls (preloading different version the issue is solved). I set this as INVALID.