error-set

[weigert@antares.mcs.anl.gov]

This refers to verrsion 1.602 of AKCL. I just noticed that si::error-set does
not behave as I would expect.
(si::error-set (car '(1 2))) returns (nil 1), but
(si::error-set (car 1)) drops us into the debugger.
I thought the point of si::error-set is just to allow to catch these
kinds of things?

Also, why does si::error-set behave exactly opposite the Franz (i.e.,
allegro excl::errorset function, in that it returns nil when form
evaluated without error rather than t?

Thanks, Thomas.