FOSS gamedev and creative worlds

I am constantly getting these errors and am wondering if there is a method to rectify them:

2015-10-18 21:09:30: ACTION[main]: Irrlicht: PNG warning: Malformed iTXt chunk
2015-10-18 21:09:32: ACTION[main]: Irrlicht: PNG warning: Interlace handling should be turned on when using png_read_image

They don't seem to affect gameplay, but I don't know.

Do you get more information about this if you run minetest --info?