Well, maybe, but we'd probably need 1) destructurable functions (so we can serialize functions), 2) some way of iterating over global variables, 3) a decent sense of 'eq?, one which returns false for distinct mutable strings, preferably in an easy eq?-key-compare association table (so we can properly/easily serialize recursive structures).

Arc-on-mzscheme actually maintains a table of globals that have been ever assigned, together with the last known arc-side assignment (IIRC it actually keeps two copies of the global, one in the table and one in the actual mzscheme global variable space).

edit:

@lboard: I also somehow doubt you want to save the whole interpreter environment; probably you just want something like this:

  (mac restartable body
    `(*restartable-f (fn (restart) ,@body)))
  (def *restartable-f (bf)
    (bf (point ret (afn () (ret self)))))

  (restartable
    (initialize-me)
    (while foo
      (if
        (some-event)
          (do-something)
        (some-error-occured)
          (restart))))

  (def my-do-something (restart)
    (if
      (some-event)
        (do-something)
      (some-error-occured)
        (restart)))

  (restartable
    (initialize-me)
    (while foo
      (my-do-something restart)))