This function can only be used on SIP channels

I am getting allot of these errors. Its not clear what the problem is?

[2014-03-13 18:28:26] WARNING[10733][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:26] WARNING[10733][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10733][C-00001ecc]: app_dial.c:2437 dial_exec_full: Unable to create channel of type ‘SIP’ (cause 20 - Subscriber absent)
[2014-03-13 18:28:27] WARNING[10734][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10734][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10734][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10734][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10734][C-00001ecc]: app_dial.c:2437 dial_exec_full: Unable to create channel of type ‘SIP’ (cause 20 - Subscriber absent)
[2014-03-13 18:28:27] WARNING[10735][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10735][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10735][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10735][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10736][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10736][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10736][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10736][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10737][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10737][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.
[2014-03-13 18:28:27] WARNING[10737][C-00001ecc]: chan_sip.c:21937 func_header_read: This function can only be used on SIP channels.

Ok, I will ask the million dollar questions, what kind of system, how was it installed and what custom channel technology (such as sccp or unistim) did you install that is generating these errors.

Let me ask you another question. Do you think we are so dense that you had to post 18 copies of the same error?