Thanks to Mike Taht work, the alignment issues on XSCALE are history.
At least with the few modules I have tried it works fine (and I had SIGBUS enabled).
As usual, I've tested the calls between SIP softphones, incoming and outgoing calls to FWD using IAX2.
When the fixes will be released (currently I've built asterisk from CVS) I will check in the makefile and patches.
The problem mentioned by KK (asterisk consuming the entire swap partition and dieing) is still happening sometimes, usually immediately after starting it on the first call attempt.
I don't know what cause this, but it looks that after it happens once and I've killed asterisk it never happens again. Usually it happens when starting asterisk after restarting the slug.