[BioC] Colours in degradation courve

[kfbargad at lg.ehu.es]

Dear users,

I am getting RNA degradation curves of 20 arrays, but the colours in 
the graph are repeated, so when I use the legend I cannot name them 
apart. 

I use col=1:length(names), and I only get 9 different colours, the 
colours are recicled, due to the default palette.
What palette could I use for 20 or more arrays? I have tried other 
palettes but some of the colours are very difficult to separate

thanks in advance,

David