POE is enabled by default are you saying its not working ?
Power over Ethernet: Cisco 300 Series Switches are available with up to 48 PoE ports of Fast Ethernet or Gigabit Ethernet connectivity. This capability simplifies advanced technology deployments such as IP telephony, wireless, and IP surveillance by allowing you to connect and power network endpoints over a single Ethernet cable. With no need to install separate power supplies for IP phones or wireless access points, you can take advantage of advanced communications technologies more quickly, and at a lower cost. Some models support both IEEE 802.3af PoE and IEEE 802.3at PoE+ while others support IEEE 802.3af PoE only