MacPorts has an older version of ECL (ecl-0.9l) that doesn't have the EXT:+ECL-VERSION-NUMBER+ causing SLIME to fail to load. The attached diff fixes this by checking for the existence of the symbol in 'swank-ecl.lisp' at read-time. I'll file a ticket with MacPorts to try to update the port. Mark -- "A screaming comes across the sky. It has happened before, but there is nothing to compare to it now."