Unfortunately, we're not sure of a great solution to actually fix the Share button on everyone's page. It's intermittent on the which pages or what sites the Share button causes conflicts, and those conflicts are with Facebook's implementation, not with JFBConnect.
It's unlikely that Facebook is going to fix this incompatibility either, as they aren't recommending the use of the Share button any longer, and are recommending the Like button with the use of special Graph API meta tags to describe the page. We'll be adding the meta tag capability into the next release of JFBConnect so that the Like button works much more like the Share button currently does.
For more information on the Share button, and Facebook's recommendation not to use it, see the top paragraph of this page:
developers.facebook.com/docs/share
We are still looking for ways to improve compatibility, but we haven't had great results yet, so far.