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#### Checklist: <!-- Go over all points below, and after creating the PR, tick the checkboxes that apply --> - [ ] PR should be backported to stable branches - [ ] Tested changes locally - [x] Related to issue #4242

#### Description <!-- Describe your changes in detail --> This PR fixes the invalid case of empy Contact.

Contact:* and expires:0 is valid and should be handled accordingly. You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/4279

-- Commit Summary --

* outbound: Use outbound if Register contains Contacts:* and Expires:0

-- File Changes --

M src/modules/outbound/outbound_mod.c (9)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/4279.patch https://github.com/kamailio/kamailio/pull/4279.diff