Why I needed \parbox and why does \framed not work here?

[Gerben Wierda <Gerben.Wierda@rna.nl>]

I am trying to convert to ConTeXt and I have a text with a lot of truth 
tables using a \ttable and \xttable command I defined. I ported these 
to ConTeXt but I can't get the \parbox -> \framed to work.

% Example document with truth tables starts here

\usemodule[bib] % defines \newcommand
\newcommand{\operand}[1]{{\sc #1}}
\newcommand{\ttvalue}[1]{{\sc #1}}
\newcommand{\xttable}[7]{\starttable[|c|c|c|]\HL %
#1 \NC #2 \NC #1 \operand{#3} #2 \SR\HL
\ttvalue{false} \NC \ttvalue{false} \NC \ttvalue{#4} \FR %
\ttvalue{false} \NC \ttvalue{true} \NC \ttvalue{#5} \MR %
\ttvalue{true} \NC \ttvalue{false} \NC \ttvalue{#6} \MR %
\ttvalue{true} \NC \ttvalue{true} \NC \ttvalue{#7} \LR\HL %
\stoptable}
\newcommand{\ttable}[5]{\xttable{a}{b}{#1}{#2}{#3}{#4}{#5}}
\starttext
Looks fine:\blank
\midaligned{%
\xttable{Statement X}{Statement Y}{$\Rightarrow$}%
{unknown}{unknown}{invalid (false)}{valid (true)}
}

This doesn't work:\blank
\midaligned{%
\xttable{Some sort of longer statement}{Another sort of longer 
statement}%
{$\Rightarrow$}%
{unknown}{unknown}{invalid (false)}{valid (true)}
}

This doesn't work either:\blank
\midaligned{%
\xttable{\framed[width=2cm,frame=off]{Some sort of longer
statement\par}}{\framed[width=2cm,frame=off]{Another sort of longer
statement\par}}{$\Rightarrow$}%
{unknown}{unknown}{invalid (false)}{valid (true)}
}
\stoptext