diff --git a/TODO b/TODO
index 55f94305..d3290e8a 100644
--- a/TODO
+++ b/TODO
@@ -36,6 +36,7 @@ Globals
 - protocols: implement CLI hooks and per-procotol CLI commands
 - protocols: implement reconfigure hook
 - protocols: use locking
+- check use of system includes and sprintf()
 
 Various ideas
 ~~~~~~~~~~~~~
diff --git a/lib/ipv6.c b/lib/ipv6.c
index 9f49be3a..b533c58c 100644
--- a/lib/ipv6.c
+++ b/lib/ipv6.c
@@ -167,12 +167,12 @@ ip_ntop(ip_addr a, char *b)
        bestlen == 6))
     {
       u32 x = a.addr[3];
-      b += sprintf(b, "::%s%d.%d.%d.%d",
-		   a.addr[2] ? "ffff:" : "",
-		   ((x >> 24) & 0xff),
-		   ((x >> 16) & 0xff),
-		   ((x >> 8) & 0xff),
-		   (x & 0xff));
+      b += bsprintf(b, "::%s%d.%d.%d.%d",
+		    a.addr[2] ? "ffff:" : "",
+		    ((x >> 24) & 0xff),
+		    ((x >> 16) & 0xff),
+		    ((x >> 8) & 0xff),
+		    (x & 0xff));
       return b;
     }
 
@@ -190,7 +190,7 @@ ip_ntop(ip_addr a, char *b)
 	{
 	  if (i)
 	    *b++ = ':';
-	  b += sprintf(b, "%x", words[i]);
+	  b += bsprintf(b, "%x", words[i]);
 	}
     }
   *b = 0;
@@ -206,7 +206,7 @@ ip_ntox(ip_addr a, char *b)
     {
       if (i)
 	*b++ = '.';
-      b += sprintf(b, "%08x", a.addr[i]);
+      b += bsprintf(b, "%08x", a.addr[i]);
     }
   return b;
 }
diff --git a/lib/resource.c b/lib/resource.c
index 98bfe4e1..e67c05a5 100644
--- a/lib/resource.c
+++ b/lib/resource.c
@@ -90,7 +90,7 @@ rdump(void *res)
   char x[16];
   resource *r = res;
 
-  sprintf(x, "%%%ds%%08x ", indent);
+  bsprintf(x, "%%%ds%%08x ", indent);
   debug(x, "", (int) r);
   if (r)
     {
diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index 4634ae1f..e885877d 100644
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -504,8 +504,8 @@ rip_dump(struct proto *p)
 static void
 rip_get_route_info(rte *rte, byte *buf)
 {
-  buf += sprintf(buf, " (%d/%d)", rte->pref, rte->u.rip.metric );
-  sprintf(buf, " t%04x", rte->u.rip.tag );
+  buf += bsprintf(buf, " (%d/%d)", rte->pref, rte->u.rip.metric );
+  bsprintf(buf, " t%04x", rte->u.rip.tag );
 }
 
 static int
diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index 1ee1c073..7857a272 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -288,7 +288,7 @@ tm_format_date(char *x, bird_clock_t t)
   struct tm *tm;
 
   tm = localtime(&t);
-  sprintf(x, "%02d-%02d-%04d", tm->tm_mday, tm->tm_mon+1, tm->tm_year+1900);
+  bsprintf(x, "%02d-%02d-%04d", tm->tm_mday, tm->tm_mon+1, tm->tm_year+1900);
 }
 
 void