A trick that gets you some of the way to different symbols: 
sysuse auto, clear
gen mymarker = cond(foreign, "o", "x") 
graph matrix weight length displacement, ///
	ms(none) mlab(mymarker) mlabpos(0) 
I don't know a way to get different colours. 
Nick 
[email protected] 
David Airey
[...] 
one cannot plot different symbols for different group  
using graph matrix
[...] 
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