I have stated the same thing many times around here...and here goes again.
This is not solely an Indexhibit problem. It's a problem with the GD library - which practially every server has installed. Most cms's have to work with this problem. Indexhibit users have always had to deal with this in their own way since day one (which has also been discussed around here and in generally on the greater web) - and people have done quite well doing so.
It is possible to make use of another library, but I am not having positive enough results with it. I can't release something that will not work and will only make things worse for people. I do not have conclusive results right now.
My mistake is that I put this problem, which once again everybody and every self hosted system has to contend with, in front of solving other problems for Indexhibit.
And I am sorry for all of this. I am so frustrated with this - all the work and testing I've done, having others try it out, seeing false positives, and I'm still not sure what to do (aside from starting a hosted version of Indexhibit so we can control everything - and we don't have the money for that).