letters coloured pink in sequence logo when alignment coloured with clustalx

Opening an alignment, showing the sequence logo and applying the clustalX colourscheme results in the sequence logo coloured pink, regardless of the colours applied to letters in each column of the alignment.

Colours of the logo should - by default - follow colours on the alignment, and default to black or white according to the background colour when the histogram is displayed.

Originally noticed by Fernando Bazan: http://www.jalview.org/pipermail/jalview-discuss/2012-May/000805.html