Odd nobody else has reported this behavior.  Have you viewed the wiki pages on this topic of running under a vm?
/b

On Mar 25, 2010, at 12:37 AM, Spencer Thomason wrote:

I dunno, just thought I'd try something different.. :-)  

root@sip:/usr/local/freeswitch/bin# uname -r
2.6.31-20-generic

I'd much rather use CentOS.  The Ubuntu machine is running under Xen 3.4.1 if that matters.