Hello,
I use the context minimal with updating to lastest beta. when using $\doteq$
in my equation, texexec catch an error:

! Illegal unit of measure (pt inserted).
<to be read again>
                   =
\buildrel ...mathrel {\mathop {\kern \zerocount #2
                                                  }\limits ^{#1}}
l.3 Test $\doteq
                $
?

I check the definition in math-pln.mkii, the \doteq is defined as:

\def\buildrel#1\over#2%
     {\mathrel{\mathop{\kern\zerocount#2}\limits^{#1}}}
\def\doteq
     {\buildrel\textstyle.\over=}

The problem seems caused by \zerocount. After comparing with the definition
in math-pln.mkiv, I changed it to \zeropoint and texexec run successfully.


Regards,
Andy