PoE driver. Not enough voltage?

Ubiquiti POE is 24v whereas standard PoE which the 5231 wants is 48v - those Ubiquiti 24v injectors are designed for their network kit which doesn't use standard PoE (although the higher end stuff does support 802.3af).
 
Damn :( I wish i knew that ha! OK, it seems ill need to buy the 48V one. Thank you!