su_root.c: fixed race condition in su_task_execute().
su_root.c: fixed race condition in su_task_execute().

Patch #1552626 by Andrzej Ciarkowski:

While running test_nua example it crashes on
su_task_execute() (called from test_nat_flush()). The
function has race condition - call to
pthread_cond_wait(frame->cond, frame->mutex); may
happen when memory pointed by frame is already
deallocated by the message dispatcher. This is clearly
visible in VC++ Debug builds, as debug version of
Windows allocator overwrites freed memory with some
rubbish, so that mutex and cond both point into
garbage. The frame probably should not be allocated as
a part of the message.

darcs-hash:20060905214600-65a35-4e95c3c1900e364e670fd4504ef54c847c425f4e.gz

erdincay/sofia-sip,BelledonneCommunications/sofia-sip,xhook/sofia-sip,unispeech/sofia-sip,unispeech/sofia-sip,unispeech/sofia-sip,BelledonneCommunications/sofia-sip,erdincay/sofia-sip,erdincay/sofia-sip,xhook/sofia-sip,xhook/sofia-sip,jart/sofia-sip,jart/sofia-sip,xhook/sofia-sip,BelledonneCommunications/sofia-sip,erdincay/sofia-sip,jart/sofia-sip,BelledonneCommunications/sofia-sip,unispeech/sofia-sip,xhook/sofia-sip