OK, so the error happens when browsing in HTTPS mode.
In other words, http://apps.facebook.com/seekjob/ works fine, but https://apps.facebook.com/seekjob/ is where it fails.
In the Facebook settings for your app, what have you defined as what they now call the Canvas URL and secure Canvas URL?
In your WordPress settings, what is defined as the Site Address or WordPress address? (in General section)
I would say you should have:
In the WPBook code, in the wpbook.php file, there are functions called fb_filter_postlink, fb_filter_postlink_no_qs, and wpbook_always_filter_postlink, starting around line 1001.
These functions all use get_option('home') to determine the home url of the blog (in wordpress) and then try to figure out the right url for an https link - maybe if you change what you have defined in WordPress as your site's home page you'd get a better result?
I think what's happening is that the functions are being too "greedy" and are picking up the "e" from seekjobsfor.me and adding it to the links for your pages.
The other solution (rather than changing your blog's home page link, would be to edit the three functions I pointed to above to add another offset++ before the offset is used?
Offhand I can't tell if the problem is the offset is one too high or one too low - it's been a long time since I was in the details of these functions.