Having some photosyntheric properties is a good idea for organic ships because it provides lots of free energy. Just like solar panels on regular ships can provide free energy. The problem with different stars could be worked out by those advanced enough in the ways of biochemistry to make such ships in the first place. Just design your clorophyl-like substance to be adaptable to different light distribution.
Although, I am skepical that that would actually even be an issue, because there are many plants that can only live in certain amounts of sunlight (such as those that can only live in the shade created by the trees of a forest), and they still use the same clorophyl.
Photons are photons, afterall.
[ December 04, 2003, 22:09: Message edited by: Imperator Fyron ]