I'm using the Shareaholic v7 plugin in combination with the custom post plugin and found that the sharing buttons are not only showing up in posts and pages, but also in my custom posts, which I don't want.
On the FAQ of the custom post plugin it's explained that this behaviour is caused by content filters not being set correctly. They link to a detailed explanation here: http://pippinsplugins.com/playing-nice-with-the-content-filter/. I'm not experienced enough to judge whether this is really the problem, but I thought I'd mention it here so you might look into it.
For now I've placed the necessary Shareaholic code manually, which works, only I can't switch the sharing buttons off for individual posts or pages this way. So I'd much more prefer to add them automatically, but would have to wait until the above issue is solved. Is this something you'd expect to be addressed in any plugin update soon?
Many thanks :)