Please, implement UPDATE command for SIP

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a) Before posting your issue you MUST answer to the questions otherwise it
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b) Please check the issue tacker to avoid duplication
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if you want quick response

What steps will reproduce the problem?
1. Try to do the call upgrade from the voice to video using UPDATE command
2.
3.

What is the expected output? What do you see instead?

I expect it to be implemented but UPDATE command is not there yet.

What version of the product are you using? On what operating system?

N/A

Please provide any additional information below.

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Original issue reported on code.google.com by `maksa...@cs.ubc.ca` on 14 Feb 2012 at 9:40