I have build linphone and dependencies (libosip2, libexosip2) for the freerunner.
You can get my packages here:
Installorder: libosip2, libexosip2, speex, linphone.
I had to recompile speex because linphone did not compile with the angstrom version (speex_1.1.12+1.2beta1-r1_armv4t), but maybe you only have to setup a softlink for it to work (start linphone by shell, like DISPLAY=:0 linphone).
This is my first build for OpenMoko, even my first crosscompilation ever. Have Fun.
(btw: I hope it works - I just started it and it looks fine :-D)
One quite important consideration: I think you have to load the correct alsastate (/usr/share/openmoko/scenarios/gsm*)