diff -r -u fetchmail-6.2.5.orig/transact.c fetchmail-6.2.5/transact.c
--- fetchmail-6.2.5.orig/transact.c	2003-10-10 22:55:05.000000000 +0200
+++ fetchmail-6.2.5/transact.c	2004-03-25 21:40:52.000000000 +0100
@@ -217,7 +217,7 @@
 	    for (sp = ok + 2; isspace(*sp); sp++)
 		continue;
 	    tp = rbuf;
-	    for (; !isspace(*sp); sp++)
+	    for (; *sp && !isspace(*sp); sp++)
 		RBUF_WRITE(*sp);
 	    *tp = '\0';