I have a Windows Vista machine that has been connecting to http://hg.netbeans.org productively for awhile... until recently.

Lately, when I attempt to pull or clone, the update appears to stall...

I see the following messages on the screen when I attempt to clone:

destination directory: web-main
requesting all changes 
adding changesets

And then... nothing happens.

I have opened the Task Manager and there doesn't appear to be any significant network activity for HOURS.

I can contact the server with FireFox and see the proper output.

I can clone from the repo with Solaris and/or Mac OS X... so the issue doesn't appear to be at the 'other end'.

I had been running a fairly old version of Mercurial before this started happening. After it started happening, I upgraded to Mercurial 1.5.2.. which did not help resolve the issue at all.

What are the likely causes and work-arounds for this?