The attached patch is a simple fix for the problem with ob-clojure using an incorrect cider-current-session call instead of cider-current-ns. For background on the issue see https://emacs.stackexchange.com/questions/30857/clojure-code-evaluation-in-org-mode-produces-no-output/31169#31169 

Not 100% convinced that the optional namespace argument should even be included - it really doesn't seem to do anything. However, leaving it in seemed like the minimal change needed.  Have tested it and at least I now get data back from evaluation of clojure code blocks where previously, you only got the message "block processed with no output". 

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regards,

Tim

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Tim Cross