Ah, ok -- scrap bb.org, then.

I tried a different hg / https:

$ /tmp/bogus/bin/hg --debug fetch osl
using https://www.open-mpi.org/hg/auth/hgwebdir.cgi/jsquyres/opal-sos/
proxying through http://proxy-sjc-2.cisco.com:80
http auth: user jsquyres, password *********
sending between command
http auth: user jsquyres, password *********
requested URL:
'https://www.open-mpi.org/hg/auth/hgwebdir.cgi/jsquyres/opal-sos/?pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000&cmd=between'
(falling back to static-http)
proxying through http://proxy-sjc-2.cisco.com:80
http auth: user jsquyres, password *********
http auth: user jsquyres, password *********
abort: requirement '<?xml version="1.0" encoding="ascii"?>' not supported!
$

Is this telling me that I need a more recent hg on the server side?  I believe
it's currently hg 1.1.1 on the server.  (forgive the n00b question...)