diff --git a/imap/make_md5.c b/imap/make_md5.c
index e404af30a5..2912c88869 100644
--- a/imap/make_md5.c
+++ b/imap/make_md5.c
@@ -38,7 +38,7 @@
  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *
- * $Id: make_md5.c,v 1.7 2008/03/24 17:09:17 murch Exp $
+ * $Id: make_md5.c,v 1.8 2008/10/02 14:05:44 murch Exp $
  */
 
 #include <config.h>
@@ -378,7 +378,7 @@ md5_mailbox_list_read(struct md5_mailbox_list *list, char *name)
 {
     struct md5_mailbox *current = NULL;
     FILE *file;
-    char buf[MAX_MAILBOX_NAME+2];
+    char buf[MAX_MAILBOX_NAME+18]; /* mboxname + uniqueid(16) + SP + CR */
     unsigned char md5_msg[16];
     unsigned char md5_cache[16];
     int len;
diff --git a/imap/make_sha1.c b/imap/make_sha1.c
index f4bac07339..c7035390f6 100644
--- a/imap/make_sha1.c
+++ b/imap/make_sha1.c
@@ -38,7 +38,7 @@
  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *
- * $Id: make_sha1.c,v 1.3 2008/03/24 17:09:17 murch Exp $
+ * $Id: make_sha1.c,v 1.4 2008/10/02 14:05:44 murch Exp $
  */
 
 #include <config.h>
@@ -381,7 +381,7 @@ sha1_mailbox_list_read(struct sha1_mailbox_list *list, char *name)
 {
     struct sha1_mailbox *current = NULL;
     FILE *file;
-    char buf[MAX_MAILBOX_NAME+2];
+    char buf[MAX_MAILBOX_NAME+18]; /* mboxname + uniqueid(16) + SP + CR */
     unsigned char sha1_msg[20];
     unsigned char sha1_cache[20];
     int len;