Thanks - you came before me. I get the same error but managed to work around.

This is likely caused by the upgrade of ess, as I realized it after
upgrading to ess 14.09.

You can work around by 
1) evaluating the R code which gives the error message
2) quitting the R session
3) re-starting the R session manually in the same window (where the old
R session was)

I also send this to the ess mailing list.

Cheers,

Rainer


Ed Kademan <ed@kademan.org> writes:

> I can't evaluate R code blocks in org files. For example the file with
> contents:
>
> #+property: header-args:R :session R-foo
>
> #+BEGIN_SRC R
>   print(pi)
> #+END_SRC
>
> spawns an R session that reports:
>
>   Error: could not find function ".ess.eval"
>
> and does not give me a result.
> I am running ess-version: 14.09 and am invoking emacs as follows:
>
> #!/bin/sh
>
> o=/usr/local/share/emacs/site-lisp/org
> emacs -Q --eval="(progn
>                   (add-to-list 'load-path \"$o\")
>                   (require 'org)
>                   (org-babel-do-load-languages
>                    'org-babel-load-languages
>                    '((R . t)))
>                   (package-initialize)
>                   (setq ess-ask-for-ess-directory 'nil
>                         ess-directory \"~/R/\"))"
>
> EdK
>
> Emacs  : GNU Emacs 24.4.50.1 (i686-pc-linux-gnu, GTK+ Version 2.24.23)
>  of 2014-08-23 on dl
> Package: Org-mode version 8.3beta (release_8.3beta-362-ga92789 @ /usr/local/share/emacs/site-lisp/org/)
>
> current state:
> ==============
> (setq
>  org-ctrl-c-ctrl-c-hook '(org-babel-hash-at-point
> 			  org-babel-execute-safely-maybe)
>  org-tab-first-hook '(org-hide-block-toggle-maybe
> 		      org-babel-hide-result-toggle-maybe
> 		      org-babel-header-arg-expand)
>  org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers
> 		  org-cycle-hide-inline-tasks org-cycle-show-empty-lines
> 		  org-optimize-window-after-visibility-change)
>  org-agenda-before-write-hook '(org-agenda-add-entry-text)
>  org-speed-command-hook '(org-speed-command-default-hook
> 			  org-babel-speed-command-hook)
>  org-babel-pre-tangle-hook '(save-buffer)
>  org-occur-hook '(org-first-headline-recenter)
>  org-metaup-hook '(org-babel-load-in-session-maybe)
>  org-confirm-elisp-link-function 'yes-or-no-p
>  org-clock-out-hook '(org-clock-remove-empty-clock-drawer)
>  org-mode-hook '(#[nil "\300\301\302\303\304$\207"
> 		   [org-add-hook change-major-mode-hook org-show-block-all
> 		    append local]
> 		   5]
> 		 #[nil "\300\301\302\303\304$\207"
> 		   [org-add-hook change-major-mode-hook
> 		    org-babel-show-result-all append local]
> 		   5]
> 		 org-babel-result-hide-spec org-babel-hide-all-hashes)
>  org-metadown-hook '(org-babel-pop-to-session-maybe)
>  org-src-mode-hook '(org-src-babel-configure-edit-buffer
> 		     org-src-mode-configure-edit-buffer)
>  org-after-todo-state-change-hook '(org-clock-out-if-current)
>  org-babel-load-languages '((R . t))
>  org-confirm-shell-link-function 'yes-or-no-p
>  )

-- 
Rainer M. Krug
email: Rainer<at>krugs<dot>de
PGP: 0x0F52F982