Dear Mike,

You can find useful information on libssh's failure to build below

http://permalink.gmane.org/gmane.comp.audio.csound.devel/27287

It seems that libssh's 0.6.3 pthread.c was written against
an aging pthread header, so I've attached a patch.

You can also try solving the problem the other way around
(which is not recommended) just to see what happens.
I have included a patch for mingw32 that restores the obsolete structure.
If you are brave enough to test it, remember not to apply (to un-patch) the
first patch.
The two patches are mutually exclusive.

-George