7048P POE 802.3at not working, Only 802.3af

I have a Powerconnect 7048P that will not power a 802.3at device.  After checking the settings in web config, it appears that there is no option to enable 802.3at, only 802.3af/legacy/both.  After checking the community, another individual experienced the same thing and indicated that there may be a beta firmware available.  Switch firmware is 5.1.16.1.  POE firmware is 4.0.1.2.