[Avodah] standing for mitzvot

[Simon Montagu]

On Tue, May 27, 2008 at 3:01 PM, Eli Turkel <eliturkel at gmail.com> wrote:
> "The Avudraham (in his siddur, weekday Shacharit) writes that there are
> six mitzvot which must be performed while standing, and their initials
> spell "alotz shalem": [the cutting of the] omer, [kiddush] levana,
> tzitzit, shofar, lulav, and mila."
>
> I thought tekiot demeushav were called that because one was not
> required to stand and it is only a minhag to stand for them.

AIUI this is precisely because the tekiot demeyushav are _not_ the
kiyyum of the mitzva d'oraita, though I only ever heard this orally
and I don't know a source. The Spanish and Portuguese minhag is in
fact not to stand for them (I'm not sure about other Sepharadim).