Is it possible to access a landline conference call with Skype?

Hi,

I have a question about attempting to use Skype to access conference calls.

I've tried to access a regular landline conference call that requires an access code using Skype before, but I called in right before the call started so didn't have much time to fool around with it, and just figured it would work. End result- Me:0 - Conference Call:1, and ending up having to call in from a landline.

I've seen where you can set up conference calls on Skype, but is it possible to access a 'normal' conference call using Skype, ie one that takes place over regular(cellular/landline) telephones? Maybe hacking/phreaking one's way in by placing the earpiece of the phone to the headset mouthpiece and punching in the access code?

Any help at all? Is there any way to do this(access a conference call) without having to pay long distance fees, ie other telephony software, etc? I am not the one setting up the call, and would just be a participant.

Thanks a bunch,
J