barely readable "autocomplete" text

Dear R users and R friends,




I have one question I wish to have answered.

I have RKWard installed on Ubuntu (12.04 LTS), and it works like a 
charm. The only problem is that the "autocomplete" function is barely 
readable.

Here, you see the parameters of "scan()" written in white, on a 
salmon-coloured background.

http://oi40.tinypic.com/20uu4r9.jpg

How and where can I change this?


Kind regards,


David