diff --git a/collects/mzlib/cm.ss b/collects/mzlib/cm.ss
index 16839d9..329e9fb 100644
--- a/collects/mzlib/cm.ss
+++ b/collects/mzlib/cm.ss
@@ -57,25 +57,25 @@
 	       (trust-existing-zos))
 	  (touch zo-name)
 	  (begin
-	    (with-handlers ((void void))
-			   (delete-file zo-name))
-	    (let ((code (get-module-code path))
-		  (code-dir (get-code-dir path)))
-	      (if (not (directory-exists? code-dir))
-		  (make-directory code-dir))
-	      (let ((out (open-output-file zo-name 'replace)))
-		(with-handlers ((not-break-exn? 
-				 (lambda (ex) 
-				   (close-output-port out)
-				   (delete-file zo-name)
-				   (let ((out (open-output-file (string-append (get-compilation-path path)
-									       ".fail")
-								'replace)))
-				     (close-output-port out))
-				   ((trace) (format "~afailure" (indent))))))
-			       (write code out)
-			       (close-output-port out))
-		(write-deps code path))))))
+	    (with-handlers ((not-break-exn? void))
+              (delete-file zo-name))
+            (with-handlers ((not-break-exn?
+                             (lambda (ex) 
+                               (delete-file zo-name)
+                               (let ((out (open-output-file (string-append (get-compilation-path path)
+                                                                           ".fail")
+                                                            'replace)))
+                                 (close-output-port out))
+                               ((trace) (format "~afailure" (indent))))))
+              (let ((code (get-module-code path))
+                    (code-dir (get-code-dir path)))
+                (if (not (directory-exists? code-dir))
+                    (make-directory code-dir))
+                (let ((out (open-output-file zo-name 'replace)))
+                  (dynamic-wind void
+                                (lambda () (write code out))
+                                (lambda () (close-output-port out))))
+                (write-deps code path))))))
     (indent (substring (indent) 2 (string-length (indent))))
     ((trace) (format "~aend compile: ~a" (indent) path)))
   
@@ -96,23 +96,26 @@
 	 (stamp stamp)
 	 (else
 	  ((trace) (format "~achecking: ~a" (indent) path))
-	  (let ((path-zo-time (get-compiled-time path))
-		(path-time (file-or-directory-modify-seconds path)))
-	    (cond
-             ((> path-time path-zo-time) (compile-zo path))
-             (else
-              (let ((deps (with-handlers ((exn:i/o:filesystem? (lambda (ex) #f)))
-			    (call-with-input-file (string-append (get-compilation-path path) ".dep")
-			      read))))
-                (cond
-		 ((or (not (pair? deps))
-		      (not (equal? (version) (car deps))))
-		  (compile-zo path))
-		 ((> (apply my-max (map (lambda (d) (compile-root d up-to-date)) (cdr deps))) path-zo-time)
-		  (compile-zo path)))))))
-	  (let ((stamp (get-compiled-time path)))
-	    (hash-table-put! up-to-date path stamp)
-	    stamp))))))
+	  (with-handlers ((exn:i/o:filesystem? (lambda (ex)
+						 ((trace) (format "~a~a does not exist" (indent) path))
+						 +inf.0)))
+	    (let ((path-zo-time (get-compiled-time path))
+		  (path-time (file-or-directory-modify-seconds path)))
+	      (cond
+	       ((> path-time path-zo-time) (compile-zo path))
+	       (else
+		(let ((deps (with-handlers ((exn:i/o:filesystem? (lambda (ex) #f)))
+			      (call-with-input-file (string-append (get-compilation-path path) ".dep")
+				read))))
+		  (cond
+		   ((or (not (pair? deps))
+			(not (equal? (version) (car deps))))
+		    (compile-zo path))
+		   ((> (apply my-max (map (lambda (d) (compile-root d up-to-date)) (cdr deps))) path-zo-time)
+		    (compile-zo path)))))))
+	    (let ((stamp (get-compiled-time path)))
+	      (hash-table-put! up-to-date path stamp)
+	      stamp)))))))
   
   (define (managed-compile-zo zo)
     (parameterize ([current-load/use-compiled (make-compilation-manager-load/use-compiled-handler)])