[NTG-context] troubles with cutafter

[Damien Thiriet]

Hello,


I went into some troubles with cutafter.
Must have missed something obvious.



\starttext
\startMPpage
path p[];
p1:= origin -- (100,0);
p2:= (50,-50) -- (50,100);
draw p1;
draw p2;
draw (p1 cutafter (p1 intersectionpoint p2)) withcolor red;

\stopMPpage
\stoptext

Can someone explain me why the whole path p1 
of this MWE is in red? I expected only its 
first half to be in red, and the whole line is.

Thanks,

Damien Thiriet