I have this for conference in the 9751-9006 Analog QRG:
Conference Call
The conference call feature allows you to connect up to eight parties,
including yourself, in a telephone conversation. The other parties
besides yourself can be on outside lines or extensions. If a called party
refuses the conference call, is busy, or does not answer, you can
reconnect to the conference. Any party can leave the conference call
by hanging up.
Note: Call the first party, then use the following steps to add each
new party.
Set up a conference call after connecting to the first party as
follows:
1. Press flash.
2. Listen for the pulse tone and the dial tone.
3. Dial the extension number, or and the outside number.
4. Inform the called party that this is a conference call.
5. Press flash again.
6. Talk to the parties.
To add more parties to the conference call, repeat steps 1-6.
Disconnect a specific party from a conference call as follows:
1. Press flash.
2. Listen for the pulse tone and the internal holding tone.
3. Dial * * 4 1 through * * 4 8, with the last
number in the code being the number of the party you want to
disconnect.
4. Press flash to reconnect to the conference call.
Reconnect to a conference if a called party refuses the call, is busy,
or does not answer as follows:
1. Hang up, or wait for the called party to hang up.
2. Talk to the parties.
I'm sorry, but I don't have any analog phone documentation for my Hicom 150 system (which is pretty close to the 3000) - all of the docs I have use at least 1 feature set button to manipulate the conference. I just logged into my HiPath 4000 and the drop party commands are exactly the same though.