image height tag removed when image is embedded #700

What steps will reproduce the problem?
Source code, in the original file: <img src="2by2.gif" width="100%" 
height="1px" />

Source code, as it shows up in the browser (Chrome, Firefox):
<img 
src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAADElEQ
VQI12NgmMkAAAE2AJohB6IfAAAAAElFTkSuQmCC" width="100%"/>

What is the expected output? What do you see instead?
<img 
src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAADElEQ
VQI12NgmMkAAAE2AJohB6IfAAAAAElFTkSuQmCC" width="100%" height="1px" />

What version of the product are you using (please check X-Mod-Pagespeed
header)?
mod-pagespeed-stable-1.3.25.4-2941

On what operating system?
CloudLinux 5.9

Which version of Apache?
httpd-2.2.3-76.el5_9.cloudlinux

Which MPM?
No

URL of broken page:
http://greenupourschools.org/application/index.php?content=application