too much recursion error - jQuery 1.4a2

too much recursion error - jQuery 1.4a2

I'm using jQuery 1.4a2 with jQuery UI 1.7.2. Creating tabs worked with
jQuery 1.3.2 as well as 1.4a1. Attempting to run $('#tabs').tabs()
with 1.4a2 results in a 'too much recursion' error. I'm not doing
anything fancy - just instantiating the tabs with a couple options.
Firebug reports the problem is on line 1486 in the Proxy function,
though I don't know enough about the internals of jQuery to verify if
this is indeed the case.
Has anyone else experienced this issue or does anyone have an idea of
what might be going on?
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