I newer can successfully implement option 43 
Here is how my DHCP configured:
ip dhcp pool wireless-ap
network 172.16.3.0 255.255.255.0
default-router 172.16.3.1
dns-server 63.139.196.34 67.151.90.2
domain-name example.com
option 60 ascii “Cisco AP c1130″
option 43 hex f104.ac19.0302 ! 172.16.3.2 in hex , 1 wc interface
but AP seems to using DNS :
*Mar 1 00:00:12.580: %LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio1, changed state to down
*Mar 1 00:00:19.704: %DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0 assigned DHCP address 172.16.3.7, mask 255.255.255.0, hostname AP001b.d561.4afe
*Mar 1 00:00:30.156: %CAPWAP-3-ERRORLOG: Not sending discovery request AP does not have an Ip !!
*Mar 1 00:00:30.571: Logging LWAPP message to 255.255.255.255.
*Mar 1 00:00:30.618: %SYS-6-LOGGINGHOST_STARTSTOP: Logging to host 255.255.255.255 started – CLI initiated
*Mar 1 00:00:33.055: %CDP_PD-4-POWER_OK: Full power – NEGOTIATED inline power source
*Mar 1 00:00:33.094: %LINK-3-UPDOWN: Interface Dot11Radio1, changed state to up
*Mar 1 00:00:33.133: %LINK-3-UPDOWN: Interface Dot11Radio0, changed state to up
*Mar 1 00:00:34.056: %LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio1, changed state to up
*Mar 1 00:00:34.094: %LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0, changed state to up
Translating “CISCO-CAPWAP-CONTROLLER.example.net”…domain server (4.2.2.1)
Translating “CISCO-LWAPP-CONTROLLER.example.net”…domain server (4.2.2.1) [OK]
*Mar 1 00:00:40.208: capwapHandleDiscoveryTimer Expired
*Mar 1 00:00:41.208: %CAPWAP-3-ERRORLOG: Did not get log server settings from DHCP.
*Mar 1 00:00:41.234: %CAPWAP-3-ERRORLOG: Could Not resolve CISCO-CAPWAP-CONTROLLER.example.netwtpDecodeDiscovery Response numOfCapwapDiscoveryResp = 0
wtpDecodeDiscovery Response numOfCapwapDiscoveryResp = 1
wtpDecodeDiscovery Response numOfCapwapDiscoveryResp = 2
*Mar 1 00:00:52.249: capwapHandleDiscoveryTimer Expired
*Mar 1 00:00:52.249: %CAPWAP-3-ERRORLOG: Go join a capwap controller
*Apr 26 00:12:31.000: %CAPWAP-5-DTLSREQSEND: DTLS connection request sent peer_ip: 172.16.3.2 peer_port: 5246
*Apr 26 00:12:32.780: %CAPWAP-5-DTLSREQSUCC: DTLS connection created sucessfully peer_ip: 172.16.3.2 peer_port: 5246
*Apr 26 00:12:32.782: %CAPWAP-5-SENDJOIN: sending Join Request to 172.16.3.2
*Apr 26 00:12:32.782: %CAPWAP-5-CHANGED: CAPWAP changed state to JOIN
*Apr 26 00:12:32.884: %CAPWAP-5-CHANGED: CAPWAP changed state to CFG
*Apr 26 00:12:33.390: %LINK-5-CHANGED: Interface Dot11Radio0, changed state to reset
