Dealing with the "height" in iOS7

After upgrading to iOS7 and iBooks 3.1.3, I can't manage to see the images correctly in my epubs. In the prevoius versions, I used a workaround to deal with the ibooks bug (ibooks did not respect heights and widths of the css file). I set a <div> with the right height percentage and its relative <img> at 100%, and that worked perfectly until now.

In the new iBooks I can't find a way to set the correct height of my images. Can you please help me?

Hundreds of ebooks made with this workaround may be useless now... How can I do?

Anybody with the same problem? I just sent a feedback to Apple, let's hope they'll work it out...

Thank you