AIS_LengthDimension text displays as solid yellow rectangle

I have a custom shape class derived from AIS_Shape that allows me to assign either a color or texture to each face. If all faces are colored (not texture mapped) my length dimensions display correctly. However, the moment I apply a texture map to any face the text of the length dimensions displays as a solid yellow rectangle instead of readable text. Has anyone experienced this problem?

Thanks for any help,

Chris