Add another error handler in the reset from to catch errors occuring

while running the servlet (perhaps with restored continuations).

scheme/httpd/surflets/surflet-handler.scm

@@ -118,6 +118,7 @@
       (register-session! instance-id 'no-return)
       
       (with-fatal-handler
+       ;; Catch conditions from get-servlet-rt-structure.
        (lambda (condition decline)
 	 (delete-instance! instance-id)
 	 (bad-gateway-error-response req path-string condition))
@@ -127,10 +128,17 @@
 				 (+ (time) (options-instance-lifetime))
 				 memo))
 	 (reset
-	  (with-cwd servlet-path
-	    (with-names-from-rt-structure 
-	     servlet servlet-interface 
-	     (main req))))))))
+	  (with-fatal-handler
+	   ;; Catch conditions that occur while running the servlet.
+	   (lambda (condition decline)
+	     (delete-instance! instance-id)
+	     ;; Restore correct continuation with shift.
+	     (shift unused
+		    (bad-gateway-error-response req path-string condition)))
+	   (with-cwd servlet-path
+	     (with-names-from-rt-structure 
+	      servlet servlet-interface 
+	      (main req)))))))))
    (else				; We'll serve every non-scm file.
     ;; We need access to SEND-FILE-RESPONSE of
     ;; HTTPD-FILE-DIR-HANDLERS. In the official SUnet release, we