Simplification triggers BUILDQ misbehavior in 5.9.1

Hi,

I have a problem with Maxima stemming from some simplification
triggered by the call to MEVAL in MBUILDQ.  The simplest example I can
find that exhibits the problem is the following, which clearly should
return just 1:

,----
| (%i1) buildq([foo: sin(bar+baz)], 1);
| 
| Maxima encountered a Lisp error:
| 
|  Type-error in KERNEL::OBJECT-NOT-LIST-ERROR-HANDLER:  MLIST is not of type LIST
`----

A simple but not very satisfactory work around is to make sure that
SIMP is FALSE:

,----
| (%i1) block([simp: false], buildq([foo: sin(bar+baz)], 1));
| 
| (%o1)                                  1
`----

This is on:

,----[ build_info() ]
| Maxima version: 5.9.1
| Maxima build date: 11:29 11/3/2004
| host type: i686-pc-linux-gnu
| lisp-implementation-type: CMU Common Lisp
| lisp-implementation-version: Snapshot 2004-10
`----


On a related note, if I want to operate on something as close as
possible to what the user entered (like with Mathematica's Hold[] or
even HoldAllComplete[]), is it sufficient to set SIMP to FALSE, or is
there anything else that may modify the input and has to be turned
off?

Regards,

Albert.