Placing/Receiving second call by putting Active Call on Hold

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What steps will reproduce the problem?
1. A calls B; A places B on Hold
2. A tries to place a call to C -- not successful
3. A is able to receive a call from C
4. Once the call is answered, unable to toggle back between the two calls

What is the expected output? What do you see instead?
A should be able to place parties on hold either manually or automatically and
be able to make and receive additional calls. There seems to be incomplete
partial support for this and additional GUI level support would be needed

What version of the product are you using? On what operating system?
Android 2.1

Please provide any additional information below.
IMSdroid v1.0.316

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Original issue reported on code.google.com by `saket...@gmail.com` on 3 Nov 2010 at 11:52