Yes but it's a little awkward.

1. Place your first call to party A.

2. Make a second call, this will put A on hold.

3. Once you are talking to B, press the Merge button on "A's" call control window. This will put you into a conference.

4. Hang up.

It should be noted that this uses a conference resource until you drop off. You'll need to ensure there are sufficient resources available.