Lets put it this way, if this magical composite material can be painted white, then it can be painted any colour under the sun.
Here is a wikipedia link that has a bit about the logo about halfway down
"On 24 July, 2007, the airline unveiled it's fifth and latest iteration of the logo, redesigned primarily to deal with technical issues arising from changes to the shape of airline tails and surface areas on stabilisers being designated as no paint areas.[48][49]"
http://en.wikipedia.org/wiki/QantasAnd this link talks about the a380 tail and mentions the paint problems with the composite material
http://www.news.com.au/heraldsun/story/ ... 62,00.html