GnomeMeeting Instruction.

Open "Tools->PC-To-Phone Account" menu.

Enter your Diamondcard.us account number and pin code.

Check "Use PC-To-Phone service".

Other links on this page allows you to recharge and control the status of your account.

Older version of GnomeMeeting.

Press Ctrl+P for opening Preference menu.

1. Fill in your personal data at "General->Personal Data".

2. Network and account settings.

Preferences -> H323 Settings ->Gatekeeper settings:

Registration method: "Gatekeeper host"
Gatekeeper host: gk.ast.diamondcard.us
Gatekeeper alias: Your Account Id
Gatekeeper password: Your PIN code
Check checkbox "Register this alias as the primary alias with the gatekeeper" 
in case your version of GnomeMeeting has this checkbox.

3. Audio settings.

Preferences -> Codecs -> Audio Codecs:

Set checkbox for GSM-06.10, G711-ALaw-64k or G711-ULaw-64k only.

4. Dial phone numbers you wish to call in international format. E.g. "18002001000" for USA +1-800-200-1000 number. No international prefix like 011 or 001 is necessary.

Other H323 clients configuration.

Gatekeeper: gk.ast.diamondcard.us
Alias or phone number: Your Account Id (which you've got on signup)
Password: Your PIN code (which you've got on signup)
Codecs: GSM, G711A, G711U.

Phone number should be sent in international format without prefixes. E.g. "18002001000" for USA +1800-200-1000 number.