Caption problem with border

Hello buddies,
I have a problem with captions on my blog. As you can see on http://www.isa-sari.com/viyana-izlenimlerim-ve-gezi-notlarim/ there is a huge space between caption text (e.g. the second image on the page, with caption “Viyana Tiyatro Binası”) and the bottom. When I cancel border from the caption’s CSS, there is no problem, but I want to use the border. How can I get rid of it?

Thank you very much for your replies in advance.