Why does !!:gs/:/ / change only one colon?

[Erik E. Rantapaa]

I want to substitute all the colons in a command line to, say, spaces in
/bin/tcsh.  However,

      !!:gs/:/ /

only changes the first colon.  Is this a bug?  Does anyone know how to get
around this?  While I've got your attention, I should also ask if anyone
has a better way to do the following in tcsh:

     echo "set today = (`date`)" > /tmp/.date
     source -h /tmp/.date
     !set:s/:/ /:s/:/ /

(note the kludge because the global sub doesn't work) but without calling
sed or writing a C program.  
-- 
Erik Rantapaa
  rantapaa at cs.umn.edu