The problem with the "tel:" in the "From:" (RFC-2806)

Good evening!

Colleagues, please tell me, how to solve my problem.

The operator provides several lines through SIP. In the “From:” field, in accordance with RFC-2806, it indicates the method “tel:”.

Asterisk refuses to accept these calls.

[quote][Feb 14 20:42:31] NOTICE[100272][C-00000005]: chan_sip.c:18130 check_user_full: From address missing ‘sip:’, using it anyway
[Feb 14 20:42:32] NOTICE[100272][C-00000006]: chan_sip.c:18130 check_user_full: From address missing ‘sip:’, using it anyway
[Feb 14 20:42:34] NOTICE[100272][C-00000007]: chan_sip.c:18130 check_user_full: From address missing ‘sip:’, using it anyway[/quote]

An asterisk is used to obtain end-line and registred in the operathor’s softswitch, instead of hardware borders.
We can not change this. Our operator cannot edit template of field “From:” and change his content.

[quote]gw-pbxCLI> core show version
Asterisk 11.2.1 built by root @ gw-pbx.host.ru on a i386 running FreeBSD on 2013-02-14 15:15:19 UTC
gw-pbx
CLI> [/quote]

From posts on this forum, I realized that at this moment Asterisk does not support described in RFC-2806 methods.

Is there a way to solve my problem?

So far I see two possibilities:

  1. Using the capabilities of Asterisk to change the content of packets from this operator. Change the “tel:” to “sip:”. Is there a functional?
  2. Exist a patch that adds a method “tel:” to the list of permissible. (His changed files parse_uri.c, check_user_full.c and get_destination.c)

Is there another way?

Ogogon.