Can I integrate ‘FreeConferenceCall.com’ with Adobe Connect?

The simple answer is ‘no’, but this is not a limitation of Adobe Connect, it is the manner in which FreeConferenceCall operates.

This is not a ‘free’ service, well it is not free to the other users on your call…this is also not a Toll-Free service and that is what Connect requires
I checked up on the FreeConferenceCall service and the paragraph below explains what is happening (it is called ‘traffic pumping’).  Depending on your perspective it is bordering on a scam in my opinion, it is a misrepresentation at best, and it is definitely not free (somebody always pays!)
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IMPORTANT – This is an excerpt from an article I found on the web.  I have not verified the details, but this seems to be in line with the experience and the business of FreeConferenceCall.com.

The Skinny on FreeConferenceCall.com
Is the audio service really free? Well, it depends on how you look at it and more importantly that you are aware of what you are actually getting…or not getting. Technically, FreeConferenceCall.com does not charge you anything. You will never get a bill from them. Who actually pays for the calls are the callers you have invited to call your number! Essentially, FreeConferenceCall.com is just free US Toll calling, meaning all callers pay their own long distance charges.
How does FreeConferenceCall.com make money? By “routing” callers to specific local exchange carriers (LEC’s) that are charging wireless carriers very high rates to “bridge” the cell calls to landlines. The higher the rate being charged, the more calls routed that way. In exchange for the favorable routing, the expensive local exchange carriers collect huge fees from the carriers and kick back a portion of the profits back to FreeConferenceCall.com Since most conference calls last at least an hour, more and more minutes accrue, while the LEC’s rake in money, siphoning dollars from the carriers.
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Even though this is seemingly free to you, it is a paid long-distance charge for all of your participants, an expensive charge from what I understand.
Adobe Connect will only work in an integrated fashion with true Toll-Free services.  You can use FreeConferenceCall with Adobe Connect, but you cannot integrate the service into your account or your meetings.
Again, this is a function of the conferencing service, Connect will not dial into this service nor can it dial others as they would have to be charged by Connect and as the service would have to charge Connect…I imagine that is why the FreeConferenceCall service does not allow Connect to dial in and behave like a Toll-Free number.
As always, you can make your own decision on the service you use.