diff --git a/cde/programs/dtmail/libDtMail/Common/DtMailRc.C b/cde/programs/dtmail/libDtMail/Common/DtMailRc.C
index 7a95e2cf3..dc0e8bc5a 100644
--- a/cde/programs/dtmail/libDtMail/Common/DtMailRc.C
+++ b/cde/programs/dtmail/libDtMail/Common/DtMailRc.C
@@ -1807,7 +1807,7 @@ int DtMail::MailRc::hash_index(char *key)
 {
     register unsigned h;
     register char *s;
-    register c;
+    register int c;
     
     s = key;
     h = 0;