[seL4] CapDL Spec Error

Hello All, Has anyone come across this error before? [GEN] imx6_net.cdl While forming CapDL spec: failed to find dataport symbol 'camkes router router_send_buf data' in ELF router_group_bin make[1]: *** [imx6_net.cdl] Error 255 make[1]: *** Deleting file `imx6_net.cdl' make: *** [imx6_net] Error 2 Thanks, Chris Guikema