This might be useful for someone. If you're on a linux box & feeling reasonably brave this command will replace all callto:// links to sip: links. A quick hack of the skype_formatted() func in utils.php to return true and enable 'skype out' in admin and your calls will click through sip applications like eyebeam etc.

AYOR:

Code:
for file in `grep -l "callto://" /PATHTOYOURSUGARDIRECTORY/* --directories=recurse`; do sed 's_callto://_sip:_g' $file >/tmp/$$ && mv /tmp/$$
 $file; done
(if your phone #'s have spaces in then you'll need to remove them first or preg_replace them in the files where they're echo'd).