Fix for old Perl in RHEL5

Partially revert a3cec180516b16ac84fc7e457cec2a03039e04bf

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>
Use additional auth field - Sip-Source-IP-Address

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>
Don't modify interim return value.

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>
Return actual payload ID in case of a dynamic payload

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>