[NTG-context] Help on \dostartbuffer needed

Hi, I'm trying to deal with \dostartbuffer. I found an old message on the ML about \dostartbuffer http://www.mail-archive.com/ntg-context@ntg.nl/msg08222.html and its is pretty what I want except that I do not know how can I get access to the buffer :) For instance, \def\startLST[#1]% {\def\stopLST{End of #1}% \dostartbuffer[LST][startLST][stopLST]} \starttext \startLST[whatever] bla bla \stopLST alb alb \stoptext will print End of whateveralb alb. I just want to get the content blabla in \stopLST. I guess, it should not be hard :) Antoine