3 way calling for CDMA (Sprint/Verizon) works differently then for GSM (T-Mobile/AT&T). Think of GSM as slow but multi-tasking. This is good for in-call features but slower for web surfing. Think of CDMA as fast but single tasking. This is bad for in call features but great for web surfing. Assuming you have GSM (T-Mobile/AT&T) you are dismissed from this thread as the call features available to you are robust and intuitive. If on the other hand you have CDMA (Sprint/Verizon) then you are probably banging your head against the wall trying to figure out how to make it work for both 3 way calling and call waiting. This thread will clear it up for you. Keep in mind, my reference is using a Blackberry on Sprint. The concepts should be useful for other phones & CDMA services as well.
Just a general overview, CDMA gives you your 1 primary call line and 1 helper line used for 3 way calling and call waiting. You do not have multiple lines like GSM (T-Mobile) phones. Since this is the case, your primary action to enable this functionality is Flashing during a call. I will walk you through the menu items but you can also use the green call button for much of this. I will describe what I think are the most convenient ways. To use 3 way calling, you must already be on a call and you must be the one initiating the 3 way call. To start the new call you must do 1 of the following 4 actions:
1) Hit the green call button to Flash to the new call line. Dial, and hit the green button again to transmit your call request. When answered, hit the green call button again to join (conference) the 2 calls. Hitting the green call button again will drop the second caller.
2) Menu->Flash... just as above from here out.
3) Menu->Conference Call. This jumps you to your contact list to choose a person to call. Once connected, hit the green call button to join the 2 calls. Just as in scenario 1, hitting the green call button again drops the 2nd caller.
4) Menu->View Address->Conference in Phone#. Like the other scenarios, once connected with the 2nd call, hit the green call button to join the 2 calls and hit the green call button 1 more time to drop the second caller.
**For all methods - Even after you drop the 2nd caller, the 2nd number dialed will display even though you are now connected with the 1st call - it's that special
**For all methods - Dealing with a failure to reach 2nd person called:
If the 2nd call does not go through or you try and join the 2nd before it's connected by hitting the green call button, you will get a fast busy signal. When this happens, hit the green call button 1 more time and you will be returned to your 1st call.
When you are on a call and a 2nd caller calls in, hit the green call button to answer the 2nd call. Hitting the green button subsequent times toggles back and forth between caller 1 and 2.
There you go. I am not an authority of any sort. It's just that I 3 way call a lot and sat down with 3 phones until I sorted this out. I hope it helps out some others.
Happy 3 way calling!